Restart the IIS and remove the temporary files :)
soap:ServerException of type 'Microsoft.SharePoint.SoapServer.SoapServerException' was thrown.Attempted to read or write protected memory. This is often an indication that other memory is corrupt. (This Post could save the time of people).
This error could occur due to memory leakage.so make sure that object is properly disposed .
Restarting IIS can resolve this issue but It may occur again If the memory leakge is not handled
Verify memory leakage scenarios here