How to resolve this System.IO.FileNotFoundException

Question

• The error only happens in production (not in debugging).
• The error only happens on the first application run after Windows login.
• The error occurs w

Answer 1

Check all the references carefully

• Version remains same on target machine and local machine
• If assembly is referenced from GAC, ensure that proper version is loaded

For me cleaning entire solution by deleting manually, updating (removing and adding) references again with version in sync with target machine and then building with with Copy Local > False for GAC assemblies solves the problem.