When release dlls don't work but debug dlls do

Question

After deploying our huge distributed system to one of our clients we experience an unexpected error. During the investigation we replace the assembly causing the error with

Answer 1

I had a similar problem. My situation like this: I defined some reflection functions in a class library A. Then I defined a WPF user control library B, which uses the functions from library A. Then I coded an application which uses the user control from library B and functions in library A. When I used the debug version of library B, it works fine. But when I used the release version of library B, the reflection functions did not work. I also defined other functions in library A. It seems that only reflection functions are causing trouble. I can not figure out the reason. Finally, I gave up and moved the reflection functions from library A to library B. And it worked.