I recently came across the above error for one of my Dynamics 365 Plugins…this blog talks about applying a quick fix.
While debugging our Plugin logic line by line to understand why it’s not working, observed this error for messages like RetrieveMultiple, Retrieve when I use any Organization Service call.
This was a .Net version downgrade issue caused by ILMerge as I downgraded one of the DLL to 4.6.2 version from 4.7.1. If you see this issue even without downgrading your DLL, you can use this fix.
After some research I came across this article and applied the same to my assembly which fixed the issue. Added these lines to my AssemblyInfo.cs class file..
Hope this helps someone who is facing the same issue down the line in their Plugin Development, Debugging…
Thank you for reading…