After I generated web service proxy using WSDL file and ran my web service client, I noticed this log:"Resolver failed to load assembly 'myAssembly.XmlSerializers.dll'". What is that?

I did not use any XmlSerializers DLL reference, or even did not know its existence until I saw XML Serializer Generator Tool:

The XML Serializer Generator creates an XML serialization assembly for types in a specified assembly in order to improve the startup performance of a XmlSerializer when it serializes or deserializes objects of the specified types.

Anyway, I added this line to "Post-build event" in Visual Studio project to generate myAssembly.XmlSerializers.dll dynamically:

"C:\Program Files\Microsoft Visual Studio 8\SDK\v2.0\Bin\sgen" "$(TargetPath)"