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Posted to log4net-user@logging.apache.org by Pete Heist <pe...@yahoo.com> on 2008/04/30 15:05:11 UTC

SmtpAppender not working on 3rd party hosting provider

I'm trying to figure out a situation where the SmtpAppender in my ASP.NET
3.5 application works properly on my development machine, but not on GoDaddy
shared hosting.

This might be easier, except that I can't see the output when
log4net.Internal.Debug = true at GoDaddy, because we have no access to, and
cannot add a listener for the System.Diagnostics output.

Some points:

- This works on my development machine with the same log4net.config.
However, in my web.config, of course, the SMTP server information is
different for development and production.

- Other logs from my RollingFileAppender appear properly, so log4net is
working.

- I know that I can send email, because a test page coded as follows in
production works:

    {
    string sFrom = "a@b.com";
    string sTo = "c@d.com";
    string sSubject = "test email to debug log4net on GoDaddy";
    string sBody = "Why are log4net email notifications not working on
GoDaddy?";

    MailMessage message = new MailMessage(sFrom, sTo, sSubject, sBody);

    SmtpClient client = new SmtpClient();

    client.Send(message);
    }

- My appender in log4net.config looks like this:

  <!-- sends an SMTP email (application log) -->
  <appender name="ApplicationSmtpAppender"
type="log4net.Appender.SmtpAppender">
    <from value="a@b.com" />
    <to value="c@d.com" />
    <subject value="Application log" />
    <bufferSize value="50" />
    <lossy value="true" />
    <evaluator type="log4net.Core.LevelEvaluator">
      <threshold value="WARN"/>
    </evaluator>
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%thread] %-5level %logger
[%property{CurrentUser}] - %message%newline" />
    </layout>
  </appender>

Does anyone either know what this could be, or have another suggestion for
debugging it short of recompiling log4net with custom instrumenting code
that writes to a file?

thanks,
Pete


RE: SmtpAppender not working on 3rd party hosting provider

Posted by Pete Heist <pe...@yahoo.com>.
It's narrowed down a bit. If I set:

<trust level="Medium"/>

on my development machine, the SmtpAppender fails silently, while my
RollingFileAppenders still work. Incidently, I've got my log4net.config file
in a separate file, rather than in my web.config file. This appears to be
working OK, but as I've seen a post about log4net configuration and medium
trust here:

http://blogs.advantaje.com/blog/kevin/Net/2006/06/29/log4Net-and-ASP-Net-Med
ium-Trust.html

it makes me suspicious.

thanks,
Pete

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com] 
Sent: Wednesday, April 30, 2008 4:09 PM
To: 'Log4NET User'
Subject: RE: SmtpAppender not working on 3rd party hosting provider

Hi Dean,

Yes, even if smtpHost is specified in log4net.config, it still doesn't send.
Looking at SmtpAppender.cs in log4net, if I set smtpHost, it's the same code
path except that the Host property on SmtpClient is explicitly set. Knowing
that my test page works without setting the Host property explicitly, I can
tell that SmtpClient is picking up the right host from the <mailSettings>
section in my web.config file anyway:

<mailSettings>
  <smtp>
    <network host="relay-hosting.secureserver.net" port="25"/>
  </smtp>
</mailSettings>

thanks,
Pete

-----Original Message-----
From: Dean Fiala [mailto:dfiala@celadonlabs.com]
Sent: Wednesday, April 30, 2008 3:54 PM
To: 'Log4NET User'
Subject: RE: SmtpAppender not working on 3rd party hosting provider

Have you tried specifiying the smtp server to use in your log4net config
file...

<smtpHost value="mail.somedomain.com" /> 

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com]
Sent: Wednesday, April 30, 2008 9:05 AM
To: log4net-user@logging.apache.org
Subject: SmtpAppender not working on 3rd party hosting provider

I'm trying to figure out a situation where the SmtpAppender in my ASP.NET
3.5 application works properly on my development machine, but not on GoDaddy
shared hosting.

This might be easier, except that I can't see the output when
log4net.Internal.Debug = true at GoDaddy, because we have no access to, and
cannot add a listener for the System.Diagnostics output.

Some points:

- This works on my development machine with the same log4net.config.
However, in my web.config, of course, the SMTP server information is
different for development and production.

- Other logs from my RollingFileAppender appear properly, so log4net is
working.

- I know that I can send email, because a test page coded as follows in
production works:

    {
    string sFrom = "a@b.com";
    string sTo = "c@d.com";
    string sSubject = "test email to debug log4net on GoDaddy";
    string sBody = "Why are log4net email notifications not working on
GoDaddy?";

    MailMessage message = new MailMessage(sFrom, sTo, sSubject, sBody);

    SmtpClient client = new SmtpClient();

    client.Send(message);
    }

- My appender in log4net.config looks like this:

  <!-- sends an SMTP email (application log) -->
  <appender name="ApplicationSmtpAppender"
type="log4net.Appender.SmtpAppender">
    <from value="a@b.com" />
    <to value="c@d.com" />
    <subject value="Application log" />
    <bufferSize value="50" />
    <lossy value="true" />
    <evaluator type="log4net.Core.LevelEvaluator">
      <threshold value="WARN"/>
    </evaluator>
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%thread] %-5level %logger
[%property{CurrentUser}] - %message%newline" />
    </layout>
  </appender>

Does anyone either know what this could be, or have another suggestion for
debugging it short of recompiling log4net with custom instrumenting code
that writes to a file?

thanks,
Pete



RE: SmtpAppender not working on 3rd party hosting provider

Posted by Pete Heist <pe...@yahoo.com>.
I found the SecurityException that's causing the SmtpAppender to fail. The
stack trace is below. (I wasn't seeing it before as I'd had
system.diagnostics redirected to a file, which was also causing a
SecurityException that I didn't see.)

Anyone know how to solve this one? Things I've tried include:

- reading configuration from web.config instead of my separate
log4net.config
- removing my GlobalContext.Properties settings and use of context
properties, thinking that the LinkDemand was happening when log4net was
calling my class to get my [%property{CurrentUser}], but apparently it's not
- setting [assembly: AllowPartiallyTrustedCallers] on my UserProvider class,
which is stuffed into GlobalContext.Properties

>From the stack, the LinkDemand appears to occur in
log4net.Util.LogicalThreadContextProperties.GetProperties(), which likely
happens when CallContext.GetData is called(?), but I'm not sure how to get
around this.

-- Begin Stack Trace --

log4net:ERROR [SmtpAppender] Failed in DoAppend
System.Security.SecurityException: Request for the permission of type
'System.Security.Permissions.SecurityPermission, mscorlib, Version=2.0.0.0,
Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.
   at
System.Security.CodeAccessSecurityEngine.ThrowSecurityException(Assembly
asm, PermissionSet granted, PermissionSet refused, RuntimeMethodHandle rmh,
SecurityAction action, Object demand, IPermission permThatFailed)
   at System.Security.CodeAccessSecurityEngine.ThrowSecurityException(Object
assemblyOrString, PermissionSet granted, PermissionSet refused,
RuntimeMethodHandle rmh, SecurityAction action, Object demand, IPermission
permThatFailed)
   at System.Security.CodeAccessSecurityEngine.CheckSetHelper(PermissionSet
grants, PermissionSet refused, PermissionSet demands, RuntimeMethodHandle
rmh, Object assemblyOrString, SecurityAction action, Boolean throwException)
   at
System.Security.CodeAccessSecurityEngine.CheckSetHelper(CompressedStack cs,
PermissionSet grants, PermissionSet refused, PermissionSet demands,
RuntimeMethodHandle rmh, Assembly asm, SecurityAction action)
   at log4net.Util.LogicalThreadContextProperties.GetProperties(Boolean
create)
   at log4net.Core.LoggingEvent.CreateCompositeProperties()
   at log4net.Core.LoggingEvent.CacheProperties()
   at log4net.Core.LoggingEvent.FixVolatileData(FixFlags flags)
   at log4net.Appender.BufferingAppenderSkeleton.Append(LoggingEvent
loggingEvent)
   at log4net.Appender.AppenderSkeleton.DoAppend(LoggingEvent loggingEvent)
The action that failed was:
LinkDemand
The type of the first permission that failed was:
System.Security.Permissions.SecurityPermission
The Zone of the assembly that failed was:
MyComputer

-- End Stack Trace --

If there are any suggestions, let me know.

thanks,
Pete

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com] 
Sent: Wednesday, April 30, 2008 4:39 PM
To: 'Log4NET User'
Subject: RE: SmtpAppender not working on 3rd party hosting provider

It's narrowed down a bit. If I set:

<trust level="Medium"/>

on my development machine, the SmtpAppender fails silently, while my
RollingFileAppenders still work. Incidently, I've got my log4net.config file
in a separate file, rather than in my web.config file. This appears to be
working OK, but as I've seen a post about log4net configuration and medium
trust here:

http://blogs.advantaje.com/blog/kevin/Net/2006/06/29/log4Net-and-ASP-Net-Med
ium-Trust.html

it makes me suspicious.

thanks,
Pete

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com]
Sent: Wednesday, April 30, 2008 4:09 PM
To: 'Log4NET User'
Subject: RE: SmtpAppender not working on 3rd party hosting provider

Hi Dean,

Yes, even if smtpHost is specified in log4net.config, it still doesn't send.
Looking at SmtpAppender.cs in log4net, if I set smtpHost, it's the same code
path except that the Host property on SmtpClient is explicitly set. Knowing
that my test page works without setting the Host property explicitly, I can
tell that SmtpClient is picking up the right host from the <mailSettings>
section in my web.config file anyway:

<mailSettings>
  <smtp>
    <network host="relay-hosting.secureserver.net" port="25"/>
  </smtp>
</mailSettings>

thanks,
Pete

-----Original Message-----
From: Dean Fiala [mailto:dfiala@celadonlabs.com]
Sent: Wednesday, April 30, 2008 3:54 PM
To: 'Log4NET User'
Subject: RE: SmtpAppender not working on 3rd party hosting provider

Have you tried specifiying the smtp server to use in your log4net config
file...

<smtpHost value="mail.somedomain.com" /> 

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com]
Sent: Wednesday, April 30, 2008 9:05 AM
To: log4net-user@logging.apache.org
Subject: SmtpAppender not working on 3rd party hosting provider

I'm trying to figure out a situation where the SmtpAppender in my ASP.NET
3.5 application works properly on my development machine, but not on GoDaddy
shared hosting.

This might be easier, except that I can't see the output when
log4net.Internal.Debug = true at GoDaddy, because we have no access to, and
cannot add a listener for the System.Diagnostics output.

Some points:

- This works on my development machine with the same log4net.config.
However, in my web.config, of course, the SMTP server information is
different for development and production.

- Other logs from my RollingFileAppender appear properly, so log4net is
working.

- I know that I can send email, because a test page coded as follows in
production works:

    {
    string sFrom = "a@b.com";
    string sTo = "c@d.com";
    string sSubject = "test email to debug log4net on GoDaddy";
    string sBody = "Why are log4net email notifications not working on
GoDaddy?";

    MailMessage message = new MailMessage(sFrom, sTo, sSubject, sBody);

    SmtpClient client = new SmtpClient();

    client.Send(message);
    }

- My appender in log4net.config looks like this:

  <!-- sends an SMTP email (application log) -->
  <appender name="ApplicationSmtpAppender"
type="log4net.Appender.SmtpAppender">
    <from value="a@b.com" />
    <to value="c@d.com" />
    <subject value="Application log" />
    <bufferSize value="50" />
    <lossy value="true" />
    <evaluator type="log4net.Core.LevelEvaluator">
      <threshold value="WARN"/>
    </evaluator>
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%thread] %-5level %logger
[%property{CurrentUser}] - %message%newline" />
    </layout>
  </appender>

Does anyone either know what this could be, or have another suggestion for
debugging it short of recompiling log4net with custom instrumenting code
that writes to a file?

thanks,
Pete



RE: SmtpAppender not working on 3rd party hosting provider

Posted by Pete Heist <pe...@yahoo.com>.
Hi Dean,

Yes, even if smtpHost is specified in log4net.config, it still doesn't send.
Looking at SmtpAppender.cs in log4net, if I set smtpHost, it's the same code
path except that the Host property on SmtpClient is explicitly set. Knowing
that my test page works without setting the Host property explicitly, I can
tell that SmtpClient is picking up the right host from the <mailSettings>
section in my web.config file anyway:

<mailSettings>
  <smtp>
    <network host="relay-hosting.secureserver.net" port="25"/>
  </smtp>
</mailSettings>

thanks,
Pete

-----Original Message-----
From: Dean Fiala [mailto:dfiala@celadonlabs.com] 
Sent: Wednesday, April 30, 2008 3:54 PM
To: 'Log4NET User'
Subject: RE: SmtpAppender not working on 3rd party hosting provider

Have you tried specifiying the smtp server to use in your log4net config
file...

<smtpHost value="mail.somedomain.com" /> 

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com]
Sent: Wednesday, April 30, 2008 9:05 AM
To: log4net-user@logging.apache.org
Subject: SmtpAppender not working on 3rd party hosting provider

I'm trying to figure out a situation where the SmtpAppender in my ASP.NET
3.5 application works properly on my development machine, but not on GoDaddy
shared hosting.

This might be easier, except that I can't see the output when
log4net.Internal.Debug = true at GoDaddy, because we have no access to, and
cannot add a listener for the System.Diagnostics output.

Some points:

- This works on my development machine with the same log4net.config.
However, in my web.config, of course, the SMTP server information is
different for development and production.

- Other logs from my RollingFileAppender appear properly, so log4net is
working.

- I know that I can send email, because a test page coded as follows in
production works:

    {
    string sFrom = "a@b.com";
    string sTo = "c@d.com";
    string sSubject = "test email to debug log4net on GoDaddy";
    string sBody = "Why are log4net email notifications not working on
GoDaddy?";

    MailMessage message = new MailMessage(sFrom, sTo, sSubject, sBody);

    SmtpClient client = new SmtpClient();

    client.Send(message);
    }

- My appender in log4net.config looks like this:

  <!-- sends an SMTP email (application log) -->
  <appender name="ApplicationSmtpAppender"
type="log4net.Appender.SmtpAppender">
    <from value="a@b.com" />
    <to value="c@d.com" />
    <subject value="Application log" />
    <bufferSize value="50" />
    <lossy value="true" />
    <evaluator type="log4net.Core.LevelEvaluator">
      <threshold value="WARN"/>
    </evaluator>
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%thread] %-5level %logger
[%property{CurrentUser}] - %message%newline" />
    </layout>
  </appender>

Does anyone either know what this could be, or have another suggestion for
debugging it short of recompiling log4net with custom instrumenting code
that writes to a file?

thanks,
Pete



RE: SmtpAppender not working on 3rd party hosting provider

Posted by Pete Heist <pe...@yahoo.com>.
Apologies for the list traffic, but this appears to have been fixed by Nicko
back in July of 2006:

http://issues.apache.org/jira/browse/LOG4NET-79?page=com.atlassian.jira.plug
in.system.issuetabpanels:all-tabpanel

http://mail-archives.apache.org/mod_mbox/logging-log4net-user/200607.mbox/%3
CDDEB64C8619AC64DBC074208B046611CC95F3B@kronos.neoworks.co.uk%3E

and targeted for version 1.2.11, which never came out. I guess I'll have to
apply his patch by hand or not use the SmtpAppender under medium trust.

thanks,
Pete

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com] 
Sent: Wednesday, April 30, 2008 6:08 PM
To: 'Log4NET User'
Subject: RE: SmtpAppender not working on 3rd party hosting provider

I found the SecurityException that's causing the SmtpAppender to fail. The
stack trace is below. (I wasn't seeing it before as I'd had
system.diagnostics redirected to a file, which was also causing a
SecurityException that I didn't see.)

Anyone know how to solve this one? Things I've tried include:

- reading configuration from web.config instead of my separate
log4net.config
- removing my GlobalContext.Properties settings and use of context
properties, thinking that the LinkDemand was happening when log4net was
calling my class to get my [%property{CurrentUser}], but apparently it's not
- setting [assembly: AllowPartiallyTrustedCallers] on my UserProvider class,
which is stuffed into GlobalContext.Properties

>From the stack, the LinkDemand appears to occur in
log4net.Util.LogicalThreadContextProperties.GetProperties(), which likely
happens when CallContext.GetData is called(?), but I'm not sure how to get
around this.

-- Begin Stack Trace --

log4net:ERROR [SmtpAppender] Failed in DoAppend
System.Security.SecurityException: Request for the permission of type
'System.Security.Permissions.SecurityPermission, mscorlib, Version=2.0.0.0,
Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.
   at
System.Security.CodeAccessSecurityEngine.ThrowSecurityException(Assembly
asm, PermissionSet granted, PermissionSet refused, RuntimeMethodHandle rmh,
SecurityAction action, Object demand, IPermission permThatFailed)
   at System.Security.CodeAccessSecurityEngine.ThrowSecurityException(Object
assemblyOrString, PermissionSet granted, PermissionSet refused,
RuntimeMethodHandle rmh, SecurityAction action, Object demand, IPermission
permThatFailed)
   at System.Security.CodeAccessSecurityEngine.CheckSetHelper(PermissionSet
grants, PermissionSet refused, PermissionSet demands, RuntimeMethodHandle
rmh, Object assemblyOrString, SecurityAction action, Boolean throwException)
   at
System.Security.CodeAccessSecurityEngine.CheckSetHelper(CompressedStack cs,
PermissionSet grants, PermissionSet refused, PermissionSet demands,
RuntimeMethodHandle rmh, Assembly asm, SecurityAction action)
   at log4net.Util.LogicalThreadContextProperties.GetProperties(Boolean
create)
   at log4net.Core.LoggingEvent.CreateCompositeProperties()
   at log4net.Core.LoggingEvent.CacheProperties()
   at log4net.Core.LoggingEvent.FixVolatileData(FixFlags flags)
   at log4net.Appender.BufferingAppenderSkeleton.Append(LoggingEvent
loggingEvent)
   at log4net.Appender.AppenderSkeleton.DoAppend(LoggingEvent loggingEvent)
The action that failed was:
LinkDemand
The type of the first permission that failed was:
System.Security.Permissions.SecurityPermission
The Zone of the assembly that failed was:
MyComputer

-- End Stack Trace --

If there are any suggestions, let me know.

thanks,
Pete

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com]
Sent: Wednesday, April 30, 2008 4:39 PM
To: 'Log4NET User'
Subject: RE: SmtpAppender not working on 3rd party hosting provider

It's narrowed down a bit. If I set:

<trust level="Medium"/>

on my development machine, the SmtpAppender fails silently, while my
RollingFileAppenders still work. Incidently, I've got my log4net.config file
in a separate file, rather than in my web.config file. This appears to be
working OK, but as I've seen a post about log4net configuration and medium
trust here:

http://blogs.advantaje.com/blog/kevin/Net/2006/06/29/log4Net-and-ASP-Net-Med
ium-Trust.html

it makes me suspicious.

thanks,
Pete

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com]
Sent: Wednesday, April 30, 2008 4:09 PM
To: 'Log4NET User'
Subject: RE: SmtpAppender not working on 3rd party hosting provider

Hi Dean,

Yes, even if smtpHost is specified in log4net.config, it still doesn't send.
Looking at SmtpAppender.cs in log4net, if I set smtpHost, it's the same code
path except that the Host property on SmtpClient is explicitly set. Knowing
that my test page works without setting the Host property explicitly, I can
tell that SmtpClient is picking up the right host from the <mailSettings>
section in my web.config file anyway:

<mailSettings>
  <smtp>
    <network host="relay-hosting.secureserver.net" port="25"/>
  </smtp>
</mailSettings>

thanks,
Pete

-----Original Message-----
From: Dean Fiala [mailto:dfiala@celadonlabs.com]
Sent: Wednesday, April 30, 2008 3:54 PM
To: 'Log4NET User'
Subject: RE: SmtpAppender not working on 3rd party hosting provider

Have you tried specifiying the smtp server to use in your log4net config
file...

<smtpHost value="mail.somedomain.com" /> 

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com]
Sent: Wednesday, April 30, 2008 9:05 AM
To: log4net-user@logging.apache.org
Subject: SmtpAppender not working on 3rd party hosting provider

I'm trying to figure out a situation where the SmtpAppender in my ASP.NET
3.5 application works properly on my development machine, but not on GoDaddy
shared hosting.

This might be easier, except that I can't see the output when
log4net.Internal.Debug = true at GoDaddy, because we have no access to, and
cannot add a listener for the System.Diagnostics output.

Some points:

- This works on my development machine with the same log4net.config.
However, in my web.config, of course, the SMTP server information is
different for development and production.

- Other logs from my RollingFileAppender appear properly, so log4net is
working.

- I know that I can send email, because a test page coded as follows in
production works:

    {
    string sFrom = "a@b.com";
    string sTo = "c@d.com";
    string sSubject = "test email to debug log4net on GoDaddy";
    string sBody = "Why are log4net email notifications not working on
GoDaddy?";

    MailMessage message = new MailMessage(sFrom, sTo, sSubject, sBody);

    SmtpClient client = new SmtpClient();

    client.Send(message);
    }

- My appender in log4net.config looks like this:

  <!-- sends an SMTP email (application log) -->
  <appender name="ApplicationSmtpAppender"
type="log4net.Appender.SmtpAppender">
    <from value="a@b.com" />
    <to value="c@d.com" />
    <subject value="Application log" />
    <bufferSize value="50" />
    <lossy value="true" />
    <evaluator type="log4net.Core.LevelEvaluator">
      <threshold value="WARN"/>
    </evaluator>
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%thread] %-5level %logger
[%property{CurrentUser}] - %message%newline" />
    </layout>
  </appender>

Does anyone either know what this could be, or have another suggestion for
debugging it short of recompiling log4net with custom instrumenting code
that writes to a file?

thanks,
Pete



RE: SmtpAppender not working on 3rd party hosting provider

Posted by Dean Fiala <df...@celadonlabs.com>.
Have you tried specifiying the smtp server to use in your log4net config
file...

<smtpHost value="mail.somedomain.com" /> 

-----Original Message-----
From: Pete Heist [mailto:peteheist@yahoo.com] 
Sent: Wednesday, April 30, 2008 9:05 AM
To: log4net-user@logging.apache.org
Subject: SmtpAppender not working on 3rd party hosting provider

I'm trying to figure out a situation where the SmtpAppender in my ASP.NET
3.5 application works properly on my development machine, but not on GoDaddy
shared hosting.

This might be easier, except that I can't see the output when
log4net.Internal.Debug = true at GoDaddy, because we have no access to, and
cannot add a listener for the System.Diagnostics output.

Some points:

- This works on my development machine with the same log4net.config.
However, in my web.config, of course, the SMTP server information is
different for development and production.

- Other logs from my RollingFileAppender appear properly, so log4net is
working.

- I know that I can send email, because a test page coded as follows in
production works:

    {
    string sFrom = "a@b.com";
    string sTo = "c@d.com";
    string sSubject = "test email to debug log4net on GoDaddy";
    string sBody = "Why are log4net email notifications not working on
GoDaddy?";

    MailMessage message = new MailMessage(sFrom, sTo, sSubject, sBody);

    SmtpClient client = new SmtpClient();

    client.Send(message);
    }

- My appender in log4net.config looks like this:

  <!-- sends an SMTP email (application log) -->
  <appender name="ApplicationSmtpAppender"
type="log4net.Appender.SmtpAppender">
    <from value="a@b.com" />
    <to value="c@d.com" />
    <subject value="Application log" />
    <bufferSize value="50" />
    <lossy value="true" />
    <evaluator type="log4net.Core.LevelEvaluator">
      <threshold value="WARN"/>
    </evaluator>
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%thread] %-5level %logger
[%property{CurrentUser}] - %message%newline" />
    </layout>
  </appender>

Does anyone either know what this could be, or have another suggestion for
debugging it short of recompiling log4net with custom instrumenting code
that writes to a file?

thanks,
Pete