RDLC Native Error 255

Question

I have an ASP.Net site running on 4.5.2, using the report viewer control. All of a sudden on our server, we are getting

An unexpected error occurred while compiling expressions. Native compiler return value: ‘255’.

This is occurring for all of our reports (Most of which haven't been modified in over a year). I am trying to identify what potentially changed and is causing this and am coming up short.

We are on Windows Server 2012.

I have found some articles pointing to an issue that occurs with some security patches. We had 4.6 installed on the server so I updated to 4.6.1 and still same issue occurs

Answer 1

So turns out that if you had installed some security patches then installed .net 4.6, it breaks the VB compiler.

I had to remove those two patches as indicated here.