I want to sync just my documents folder with an external drive, but I don’t want documents removed from the drive in case I need to restore them. What should I do?

You can accomplish this in short order with the freeware version of SyncBack and our guide to automatically backing up your hard drive , but we’ll go over the important settings here—the key to doing a one-way backup is located in the profile setup screen, where you will first choose to backup everything under the directory:

And then on the screen you’ll find the important setting: make sure that “What to do if a is in the destination but not in the source” is set to “Do nothing”, which will leave your backup files alone even if they have been removed from your documents folder.

3b886285fbkThumb.png How Do I Setup a One Way File Sync Backup?

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How Do I Setup a One-Way File Sync Backup? [Ask Lifehacker]