Filter Processing Error

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Description: An unhandled exception occurred during the processing of a filter notification. Please review the stack trace for more information about the error and where it originated in the code.

Event Details:
   Event: PreProcHeaders
   Instance: KodeIT.Web.Samples.ServerHeaderChange, KodeIT.Web.Samples, Version=1.2.9364.31466, Culture=neutral, PublicKeyToken=null

Process Details:
   Id: 10508
   Name: w3wp.exe
   Account: NT AUTHORITY\NETWORK SERVICE

Exception Details: IOException: ???????

Stack Trace: 


   ? System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
   ? System.IO.FileStream.WriteCore(Byte[] buffer, Int32 offset, Int32 count)
   ? System.IO.FileStream.FlushWrite(Boolean calledFromFinalizer)
   ? System.IO.FileStream.Dispose(Boolean disposing)
   ? System.IO.Stream.Close()
   ? System.IO.StreamWriter.Dispose(Boolean disposing)
   ? System.IO.TextWriter.Dispose()
   ? KodeIT.Web.Samples.Function.OnLog(String logstr, String prefix)
   ? KodeIT.Web.Samples.ServerHeaderChange.OnPreProcHeaders(Object sender, PreProcHeadersEventArgs e)
   ? KodeIT.Web.InstanceEvents.OnPreProcHeaders(PreProcHeadersEventArgs e)
   ? KodeIT.Web.Hosting.ProxyInstance.KodeIT.Web.Hosting.IProxyInstance.OnPreProcHeaders(IProxySession session, IntPtr contextPtr, IntPtr eventPtr, FilterEvent eventType)

Version Information: Filter.NET Framework Version: 1.0.1.0; .NET Version: v2.0.50727