Installing and upgrading help

Thanks to Tim I was able to find the problem and after talking to teachers I found they were copying and pasting from old word worksheets into the the quiz  to make their questions.  There is a lot of questions this way.  Does anyone have a suggestion on what to do to get it out of the database.  I have tried going through and cleaning up the questions I think very thoroughly.  I really could use some help. The weird thing is that I can update from 1.9.7 to 1.9.10+ without a problem