Dear Danaan,
Just a thought, but have you tried opening the file with Option 2 :Select Data file to share, instead of Option 1: Select data file. It might make a difference.
Also, to the person with the corrupted file problem - try the following. First, select the corrupt file and use option 4 sub option 2 to copy the form design under a different name. Secondly use option 6 sub-option 4 to try to recover the data records - WARNING do not give the "recover to" file the same name as either the empty form design OR the original file itself or you will loose it! Recovery can take a while, depending on the size of the drive the file lives on, so go and have a tea or coffee or something! If sucessful, you will end up with a set of records that you can copy into the empty form design, thus recreating the original file. I have had this problem now and then, all I can say is BACKUP YOUR DATA FILES AFTER EVERY SIGNIFICANT CHANGE! It does seem slightly more likely to happen in files with many indexes, large files approaching the 8 meg limit, and files where there have been repeasted replace operations - if any of these things are true it is a good idea to compact your file(s) regularly by using main menu option 1 sub option 2 or 3 (it doesn't matter which if you're not making any changes) this process will purge the filespace of any deleted records and recreate all the indexes from scratch. Again before doing this ALWAYS MAKE A BACKUP COPY OF THE ORIGINAL FILE - JUST IN CASE!
Best of Luck,
Jacq.