b4f569c4_ips__Converting_to_Access_2007__Bug
[Comments] If you have an AutoNumber field that is not the primary key, Access 2007 allows an Update query to update the field to Null. When you compact the database, you then lose all records in this table. [Fixed?] Yes: SP2 [Bug] 
Data loss on compact
Microsoft Access tips: Converting to Access 2007
Bug