Error: The transaction could not be locked. It is in use by another user.

QuickBooks error message: The transaction could not be locked. It is in use by another user.

This error occurs when the transaction that you wish to modify in QuickBooks is already in use by another user or the QuickBooks database has temporarily locked the transaction for editing or update.  Requesting that the user completes there editing and closes that process normally enable the transaction to be modified on a subsequent import.  If you encounter these errors regularly then by switching the company file to single user mode and closing QuickBooks windows should minimise the occurences.