QuickBooks uses a transaction log file to track changes to your data since
the last time you backed up your company file, provided you have set a verification level. In case of an accidental data
loss, Intuit Technical Support can use your transaction log file, in conjunction
with your most recent backup, to recover your data up to your most recently
saved transactions. For more information about data recovery, contact Intuit
The transaction log file is also created if you sync your QuickBooks data with
certain online services using Intuit Sync Manager.
In this case, the transaction log file allows ongoing syncs to happen much more quickly
than the initial full upload of QuickBooks data into your online services.
The transaction log file has the same name as your company file, but with a
.qbw.tlg extension. For example, MyCompany.qbw has a transaction log file named
Back up company files
Restore company files
Intuit Sync Manager overview