参数名称：在插件程序集中找不到插件类型

Question

I've developed a plugin for Dynamics CRM 2011 on-premises using developers toolkit. I've not updated the default code and simply deployed it. But I receive exception. I don't what is the problem with it. Following is the Exception Details.

Unhandled Exception: System.ServiceModel.FaultException`1[[Microsoft.Xrm.Sdk.OrganizationServiceFault, Microsoft.Xrm.Sdk, Version=5.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35]]: System.ArgumentNullException: Value cannot be null.
Parameter name: The plug-in type could not be found in the plug-in assembly: STGDevPlugin.Plugins.PreValidateAccountCreateDetail: 
<OrganizationServiceFault xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.microsoft.com/xrm/2011/Contracts">
  <ErrorCode>-2147220970</ErrorCode>
  <ErrorDetails xmlns:d2p1="http://schemas.datacontract.org/2004/07/System.Collections.Generic" />
  <Message>System.ArgumentNullException: Value cannot be null.
Parameter name: The plug-in type could not be found in the plug-in assembly: STGDevPlugin.Plugins.PreValidateAccountCreate</Message>
  <Timestamp>2015-08-03T10:43:33.5989514Z</Timestamp>
  <InnerFault i:nil="true" />
  <TraceText>

[STGDevPlugin.Plugins: STGDevPlugin.Plugins.PreValidateAccountCreate]
[7122c821-cc39-e511-8aa3-005056b04acd: PreValidateAccountCreate]


</TraceText>
</OrganizationServiceFault>

Answer 1

Could you verify that you have the same DLL version of

Microsoft.Xrm.Sdk and Microsoft.Crm.Sdk

included in your GAC?

You probably have 5.0.0.0 in your GAC and 6.0.0.0 in your solution or the other way around.