Hi Suzanne,
This really isn't possible. Once you were to sync another QuickBooks file, you would lose much of the data that is already in Method. Since the QuickBooks listID's would be different, most of the records would be lost, as Method would not be able to sync them to the current QuickBooks file. This would cause DeleteFromDesktop conflicts and errors in Method. Along with that, any custom fields in the old QuickBooks file would no longer be linked causing other data loss and errors.
Why do you want to create a new file? If Full Syncs are taking longer than before, you can adjust the transaction history range, and therefore shorten the syncing time.
- Adam