Question: During a Pack I got "Error 41, memo file is missing or invalid". What does this mean? Answer: One of the project or library memo files may be damaged. Restore from a recent backup. If no recent backup, make a current backup and then try creating a duplicate project. To create a duplicate project, from the File menu, choose Save As. Select Ultimate Family Tree Project as the File type. Enter a new name in the file name field and choose OK. If neither of these work, contact Technical Support (Yea what Tech Support)
This error may be the reason that the file grew as something was added to a file. Did the power go off or UFT didn't get closed right?
If you do the above I would be sure in the new project to check your sources and places.