The error 6129, 0 can occur on different conditions and differ according to execution type. Here, we have two situations and their solutions that can initiate the error code 6129, 0.

How to fix this QuickBooks Error 6129, 0Situation 1: Error while opening or <a href="https://www.askforaccounting.com/quickbooks-the-company-file-needs-to-be-updated/">updating company file</a>

The first step for this condition is opening a sample company file and recognizing whether it is a file-related issue. Move to the steps given steps, once the company file issue is verified.

Solution 2: Disable Antivirus and other SoftwareDisable any active antivirus on the computer.Restart the computer on “Windows Safe Mode.”Open QuickBooks and add a new company file. Restart the computer in normal mode. Open the QuickBooks company file again and check its proper functioning. 
Solution 2: Rename QuickBooks Network (.ND) FilesOpen File manager and go to C-drive (default drive for installed programs). Click on the QuickBooks folder files. Check for files with the “.nd” extension. Go to the “.nd” files, rename all the files, and add “.OLD” on all network files. 

If you use QuickBooks in multi-user mode, rename network files for all individual devices. 

Open the QuickBooks Database server manager and click on “Scan Folders.”

Click “Add new folder” on the QuickBooks database server manager if you do not find the company file after the scan.  

Once you have completed all the steps, open the company file and check whether it is properly functioning. 

If still getting an issue get more steps to resolve the <a href="https://www.askforaccounting.com/quickbooks-error-6129-support/">error QuickBooks 6129</a>.