Games disappeared after a drive change

Updated: 2026-08-25

The files are still there. Steam navigates by a list of library paths, and when a path stops resolving the whole library drops out of the client at once — which looks a great deal worse than it is.

What happened

Steam keeps every library folder it knows about in libraryfolders.vdf. It does not go looking for games; it reads that list. If the path in the list no longer resolves, the games in it are simply not there as far as the client is concerned.

Three things cause it, and all three leave the games completely intact:

Windows handed the drive a different letter, usually after adding another disk or a card reader.
An external drive was reconnected to a different port and came up as a different letter.
The drive was cloned or migrated and the new one mounted somewhere else.

Get them back

Confirm the files exist. Open the drive and look for steamapps\common with the game folders inside. If they are there, nothing has been lost.
In Steam, open Settings → Storage, click the drop-down and choose Add Drive. Point it at the drive — at the root, not at steamapps.
Restart Steam. The library is re-read at startup and the games should be listed again.
If they are listed but Steam offers to download them anyway, the manifests are missing rather than the library. Steam needs appmanifest_<appid>.acf in steamapps for each one.
As a last resort, let Steam start the download and stop it after a second: it creates the manifest, and on finding the files already present it switches to verifying instead of downloading.

That last trick is slow to explain and takes about ten seconds to do. It works because Steam validates against what it finds on disk rather than assuming an empty folder.

Restoring the old drive letter

Often cleaner than re-adding, because everything else that referenced the old path keeps working too. In Windows: right-click Start → Disk Management, right-click the partition → Change Drive Letter and Paths → set it back to what it was. The letter must not already be in use.

What not to do

Do not clean up library entries while the drive is merely disconnected. An unplugged drive and a deleted one look identical from inside Steam — the path does not resolve in either case. Anything that tidies away "dead" entries automatically will happily remove a perfectly good library because a USB disk was not plugged in that morning.

Also: do not delete libraryfolders.vdf to "make Steam rebuild it". Steam will make a new one containing only the default library, and every other library then has to be added back by hand — with the manifest problem above waiting at the end of it.

And do not edit it while Steam is running. The client rewrites the file on exit and your changes go with it.

Act on it

Vapor Storage Manager detects library entries whose path no longer resolves and shows which games each one holds before anything is changed. It re-checks the path at the moment it writes, and backs the file up first — because a drive that is unplugged today is usually plugged back in tomorrow.

Download Vapor Storage Manager