Add-In Initialization Error when launching Microsoft Dynamics GP 2010

Lately, many users have reported getting the error depicted below after launching Microsoft Dynamics GP 10 with Service Pack 5 or Microsoft Dynamics GP 2010 with Service Pack 1:  Add-In Initialization Error The error references the Microsoft.Dynamics.GP.OnlineServices.dll  assembly file as the root cause of the problem. This assembly was shipped with Microsoft Dynamics GP 10 SP5 and is a part of the Dynamics Online Services application. The error typically indicates that the add-in assembly is loaded, however, it most likely indicates that the Dexterity portion of the application, dictionary DO6499.dic , isn’t loaded in the path found in the DYNAMICS.SET file — which should have also generated a dictionary load error prior to receiving the above message — or isn’t loaded at all.

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Add-In Initialization Error when launching Microsoft Dynamics GP 2010