QuickBooks Desktop 2019 Company File Types and What to Back Up

Last reviewed 2026-07-05 4 min read

QuickBooks Desktop 2019 creates several file types. Learn what .QBW, .QBB, .QBM, .ND, and .TLG files do and exactly which ones you must protect.

If you are still running QuickBooks Desktop 2019, you are managing software that officially passed its discontinuation date on May 31, 2022. While the software continues to function offline, Intuit no longer provides updates, add-on services, or live support for this version. Because you are now maintaining this system entirely on your own, understanding the files QuickBooks creates—and knowing exactly which ones to protect—is critical to your long-term survival.

Here is a breakdown of the file types generated by QuickBooks Desktop 2019 and how to manage them.

The Primary Working File (.QBW)

The .QBW file is your actual QuickBooks company file. It contains every transaction, customer record, vendor detail, and report configuration you have ever entered. This is the file QuickBooks opens every time you launch your daily work.

Because it is the live database, it is also the most susceptible to corruption from sudden network drops, improper shutdowns, or hard drive failures. You must protect this file, but you should never back it up by simply copying the .QBW file while QuickBooks is running, as doing so can capture the database in an incomplete state and cause permanent damage.

The Backup File (.QBB)

The .QBB file is a compressed backup of your .QBW file. This is the single most important file for your long-term data protection.

Creating a .QBB file packages your financial data safely and compresses it to save disk space. Even though QuickBooks 2019 is sunsetted and no longer connects to Intuit's servers, you can still use the software's internal backup tool to generate .QBB files locally or on an external drive. If your live company file ever fails, a recent .QBB file is your fastest path to recovery.

The Portable Company File (.QBM)

A .QBM file is a highly compressed version of your company file designed specifically for easy transfer. It strips out some of the background database bulk (like temporary log files) to make the file size as small as possible.

If you ever need to move your 2019 accounting data to a new computer, or send a copy of your books to an accountant or tax professional who also runs Desktop, the .QBM format is the most efficient way to do it. Once opened on the receiving end, QuickBooks expands the portable file back into a fully functioning .QBW file. It is an excellent tool for mobility, but it does not replace the need for a full .QBB backup.

The Network Data File (.ND)

The .ND (Network Data) file is a configuration file used by the QuickBooks Database Server Manager. It tells QuickBooks how to communicate with the company file across a network, allowing multiple users to access the file simultaneously.

You do not need to back up .ND files. If they are deleted or become corrupted, QuickBooks can easily rebuild them. If you ever move your 2019 company file to a new server or a new local drive, you will likely need to delete the old .ND file and run the Database Server Manager to scan the folder and generate a fresh one.

The Transaction Log File (.TLG)

The .TLG file is a continuous transaction log. Every time you enter, edit, or delete a transaction in QuickBooks, that action is recorded in the .TLG file before it is fully written to the main .QBW database.

Under normal, supported conditions, Intuit uses the .TLG file alongside their Auto Data Recovery feature to restore a company file if it suddenly crashes. Because QuickBooks 2019 is discontinued, you should not rely on the .TLG file for emergency recovery, as the built-in recovery tools are no longer updated by Intuit and can be unreliable on modern operating systems.

You do not need to back up the .TLG file. In fact, if you ever need to manually restore a .QBB backup, you will delete the existing .TLG file so QuickBooks does not get confused by old, mismatched transaction logs.

Which Files to Protect for the Long Haul

To keep your accounting history secure on a discontinued version of QuickBooks, your focus should be narrow:

Always maintain current .QBB backups. Set a routine to create these locally or on an external drive at the end of every business day or week.
Keep your .QBW file on a stable, local drive. Avoid running your live company file directly from a cloud-synced folder (like OneDrive or Dropbox), as background syncing processes frequently corrupt live QuickBooks databases.
Ignore the helper files. Let QuickBooks manage and regenerate .ND and .TLG files as needed.

If your live .QBW file ever throws a critical error (such as a -6000 series code) or refuses to open, do not panic. As long as you have a recent .QBB backup, you can restore your books to a functional state. For situations where your backup is outdated and the live .QBW file is throwing structural errors like target chaining failures or unreadable data, specialized QuickBooks company file repair services can often rebuild the damaged database structure without forcing you to upgrade your software.