From an old KB article.....
Possible Workarounds:
If a backup is available from prior to the Custom Office installation, restore the following files to the ..\Mas90\Mas_System folder::
CM_UDF.M4T
CM_Entity.M4T
CM_UDFIOList.M4T.
If no backup is available, reinstall all modules that have a Product Key.
Recreate every UDF for all modules except General Ledger. (The General Ledger UDF's should still be intact.)
Note: The UDFs must be recreated in the same order as they existed on the prior version.? If the UDF's are not listed alphabetically, then each UDF will have to be updated before adding the next one. The UDFIOList has to be the same order as the UDF's so that it points to the correct field in the UDF file.
If the data has just been migrated from a prior version:
Install Sage MAS 90 4.0 to a new location and migrate the files to that installation.
Note: Do not delete the existing installation.
Copy all five CM_*.M4T files from the new ..\Mas90\MAS_System folder to the existing installation.
Note:? The new installation can be deleted once this procedure is performed.