I can't get rid of Microsoft Visual Basic 400

I have four worksheets in my workbook with essentially the same macro formulas. However for sheets three and four the shortcuts to run macros isn't working and I am getting a dialogue box that reads visual basic 400.

Is there any reason outside of a coding error that this would come up as I have gone through my lines of code and don't see an error

Note: The worksheets 3 and 4 are a little more complicated and the sheet was designed on an older version of excel and has been susquently copied into excel 2007

I'm fried. Thanks in advance for any help.