• The computers running in the multi-user mode have not updated to the latest release.
• There is a mismatch between the Client domain and Server.
• Corrupted/Damaged (.ND) Network data file.
• The Company file upgraded to the QuickBooks Latest Version with Non-windows admin profile.
• A third -party Anti-virus is causing the QuickBooks Error 6129 0.
Hopefully, QuickBooks Error 6129
is fully resolved, and you are smoothly working on your QuickBooks. If the problem, is still persistent and did not go away even after trying all of the solutions provided above, you can call a certified QuickBooks Error Support Number +1-855-977-7463 to resolve the issue.