Test disabled - results slide at fault?

I had an issue where I had four tests within a module. The user was able to access them in any order depending upon the topic they had chosen. The problem I had was that one of the tests would work fine if it was accessed first, but would be disabled (the multichoice questions couldn't be selected at all) if it was accessed after any of the other tests. I eventually replaced the results slide that was associated with the questions of that particular test and it seemed to fix the problem. Just an FYI if anyone else has the same issue.