I’ve said it before, but it can’t be said too often. Backups need to be tested regularly. An unreliable internet connection, a failing USB cable, a drive at full capacity – these are just a few of the reasons a backup may be corrupt.
No matter how good your online backup service is (and the online backup service we recommend is VERY good), no matter what the warranty on your external hard drive, no matter how many flash drives you swap out, you cannot ever be certain there is good data in that backup unless you check it regularly.
How often your backup should be checked depends on how critical your data is. For small businesses and sole proprietors, we recommend a checkup at least once every month or two. For residential customers, that can be stretched to six (again, depending on how critical the data is and how often you’re backing up new files).
When you check the content of your backup, you should also check that what you are backing up doesn’t need editing. Perhaps you’ve added a new source of data, such as a new Outlook profile or a Quickbooks file, since your backup was initially set up. Make sure your backup software is set to back up everything that you need it to.