We have repaired many sets of damaged QuickBooks accounting data over the years and we are often asked “How did this happen?”

Good question! Here are some of the most common causes of QuickBooks data damage:

  • Network glitches. You are using QuickBooks across a network in multiuser mode. One of the workstations loses connection with the server for a moment and then reestablishes connection. During the disconnecting and reconnecting, the data stream gets changed a bit, and the database gets corrupted.
  • Performance bottlenecks. If your QuickBooks data file is huge and you have a lot of people in QuickBooks at the same time and your computers are old, QuickBooks is not going to be able to keep up with all the read and write requests to the database. The file will get damaged at some point.
  • Power blips. If the power momentarily goes out in your office, it can change data and corrupt the QuickBooks database. Most users have their server protected with battery backups, but many don’t protect their desk computers or network routers with battery backups. Uninterruptable Power Supplies (battery backups) are cheap insurance.
  • Disk crashes. Hard drives have moving parts, and like any mechanical device, they will fail at some point. If the only copies of your data are on your hard drive, that’s a recipe for disaster.
  • Bad software. Malware, spyware, viruses, worms, trojans…if your computer gets sick, it can affect QuickBooks and other applications you depend on.
  • User error. Just kidding! Users can’t really trash or crash their database unless they do something silly like unplugging the power or a network cable while QuickBooks is running. You can’t mess up the database by doing normal processes within QuickBooks itself.

To prevent data corruption in QuickBooks, you basically want to do whatever you can so that QuickBooks can read and write to its database quickly and without any interruptions. You also want to regularly backup your data to a location OFF your hard drive.

If you somehow find yourself with data errors in QuickBooks and no current backup, AccountingUsers Inc. provides fast, guaranteed data repair services.

What did I miss? Any other known causes of QuickBooks data damage you know of?

Please follow and like us:

There are some QuickBooks data situations that have good endings, and some that don’t.


  • -6000 errors. If you get a 6000 error when you try to open your company file, most of the time if means that your data is corrupted, but most of the time, it is also repairable.
  • “Connection to database lost” errors. Ditto above.
  • Errors triggered when accessing particular accounts or transactions. Same.
  • Failures during upgrades, backups, verifies, rebuilds. We can fix these.
  • For pre-2006 QuickBooks versions, c-342, c-43, c-44 errors are almost always repairable.


  • -6150 errors. This error usually indicates hopeless file corruption. A critical area of the file has become damaged that is not reconstructable. Although this error indicates that the QBW file is unrecoverable, we can still help you if you have an old but good backup and a current TLG file.
  • Files recovered from damaged or reformatted hard drives. This situation is common, but unfortunately, does not usually have a good outcome for data repair. Files recovered from damaged or reformatted HDs, or undeleted from drives, often have random contents — not the original QuickBooks data that was there in the first place. I don’t know why that is, but I’ve talked to a lot of users and IT people over the years with this situation, and that seems to be the case about 90% of the time that people contact us.

A quick way to test the recoverability of a file recovered from bad media is to zip the recovered file with WinZip or Windows folder compression. In a lot of cases, the file will zip up 99%. For example, a 100MB QBW file will zip down to 1MB. That indicates that the original contents of the file did not get recovered properly, and you ended up with a QBW file full of zeroes.

    Please follow and like us: