.NET XML Serializer misbehaver (G.S.)

From time to time your asp.net web service might crash with an wired error that says a certain .dll file is missing or that it cannot create a certain .dll in the TEMP folder. Those DLL files have generated names and if you receive one of these symptoms and the DLL file looks like a virus name then know that you had bad luck. As Microsoft says this happen only "sometimes".

The reason is that the XmlSerializer creates C# files (.cs files) and compiles them into .dll files in the directory named by the TEMP environment variable; serialization occurs with those DLLs. So what you can do is to set permissions on the TEMP folder to the ASPNET user or to the user that is running the web service.