On one of my machine i have installed the Business Intelligence which deploy the DLL in Addins Folder. After that i am able to login in Dynamics GP2010.
We have created a Addon which also get install in Addins Folder, but after installing the Addon when we try to login in GP 2010 on login screen we get the followinf error
Microsoft.Dynamics.GP.BusinessIntelligence.BIReportDeploymentGP.dll : Method Not Found 'ClearCompanyListProcedure FormProcedures.get_ClearCompanyList()'.
This is an issue with your custom add-in. You would need to contact the Dexterity team to assist with this.
After removing Application.Dynamics.dll from Addins Folder problem resolved.
That was the clue I needed for my issue, actually .dll version problem...