So you lost a thumb drive containing a git-annex repository. Or a hard
drive died or some other misfortune has befallen your data.

Unless you configured backups, git-annex can't get your data back. But it
can help you deal with the loss.

First, go somewhere that knows about the lost repository, and mark it as
untrusted.

	git annex untrust usbdrive

To remind yourself later what happened, you can change its description, too:

	git annex describe usbdrive "USB drive lost in Timbuktu. Probably gone forever."

This retains the [[location_tracking]] information for the repository.
Maybe you'll find the drive later. Maybe that's impossible. Either way,
this lets git-annex tell you why a file is no longer accessible, and
it avoids it relying on that drive to hold any content.