Cannot execute a program csc.exe when calling a webservice from as

[Simone Chiaretta]

I'm having a problem with webservices:
from times to times I get the following error (incapsulated in a SOAP Exception)

It seems like each time I call a webservice, something is auto-generated and then compiled.
I saw a KB article about a problem with asmx called from aspx: a problem caused by IIS lockdown restricting too many access. But we never used it...
Also we verified that the account that the webservice is running with (the IUSR_machine user since we used impersonation) has execue access to the dir where exe are, and also to temp directories and so on...

In fact the problem happens only a sometimes, not with every call.

The only way to resolve the problem is to recycle the working process.
How can I solve this problem?
Is this a bug with Serializer?

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System.Runtime.InteropServices.ExternalException - Cannot execute a program. The command being executed was "c:\windows\microsoft.net\framework\v1.1.4322\csc. exe" /noconfig @"C:\WINDOWS\TEMP\f8evjsge.cmdline". on System

Error details:

at System.CodeDom.Compiler.Executor.ExecWaitWithCaptu reUnimpersonated(IntPtr userToken, String cmd, String currentDir, TempFileCollection tempFiles, String& outputName, String& errorName, String trueCmdLine)

at System.CodeDom.Compiler.Executor.ExecWaitWithCaptu re(IntPtr userToken, String cmd, String currentDir, TempFileCollection tempFiles, String& outputName, String& errorName, String trueCmdLine)

at System.CodeDom.Compiler.CodeCompiler.Compile(Compi lerParameters options, String compilerDirectory, String compilerExe, String arguments, String& outputFile, Int32& nativeReturnValue, String trueArgs)

at System.CodeDom.Compiler.CodeCompiler.FromFileBatch (CompilerParameters options, String[] fileNames)

at System.CodeDom.Compiler.CodeCompiler.FromSourceBat ch(CompilerParameters options, String[] sources)

at System.CodeDom.Compiler.CodeCompiler.FromSource(Co mpilerParameters options, String source)

at System.CodeDom.Compiler.CodeCompiler.System.CodeDo m.Compiler.ICodeCompiler.CompileAssemblyFromSource (CompilerParameters options, String source)

at System.Xml.Serialization.Compiler.Compile()

at System.Xml.Serialization.TempAssembly..ctor(XmlMap ping[] xmlMappings)

at System.Xml.Serialization.XmlSerializer.FromMapping s(XmlMapping[] mappings)

at System.Web.Services.Protocols.SoapClientType..ctor (Type type)

at System.Web.Services.Protocols.SoapHttpClientProtoc ol..ctor()

at com.esperia.publishing.AdminWS.admin..ctor() in N:\SourceSafe\s.chiaretta\EspPublishing.NET\Web References\AdminWS\Reference.cs:line 30

at com.esperia.publishing.NewsItem..cctor() in N:\SourceSafe\s.chiaretta\EspPublishing.NET\NewsIt em.cs:line 39ù

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