VBA application not saving properly
 

I've developed a VBA application in Excel which launches a form when it
opens. Each time I save the file and then try to open it up again, a message
pops up saying that the file was not saved correctly. I have to disable the
macros and save the file. The next time I try to open it, it works. This
pattern of opening, saving it and then having to save it again with the
macros disabled repeats evry time. Any ideas?