Android .ab backup won't restore: extract the files without a phone
Last reviewed 2026-09-19
An Android backup (.ab) made with adb backup is a short text header followed by a TAR archive, usually zlib-compressed. If the phone is gone, the restore tool rejects it, or the file was cut off, the files inside can often still be pulled out directly.
Messages you might see
- “adb restore fails or does nothing”
- “Invalid backup / Can't restore the .ab file”
Why it happens
- The phone the backup was made on is lost or broken, or you only want a few files.
- The backup was interrupted, so its compressed stream is cut off.
- The backup is encrypted with a password.
Try this first (free, no tool needed)
- Open the file in a text editor and look at the first four lines: they show the format version, whether it is compressed and whether it is encrypted.
- If the fourth line says AES-256 the backup is encrypted. Open-source tools such as Android Backup Extractor can decrypt it if you know the password.
- If it is not encrypted, the open-source "abe unpack" command turns it into a TAR you can open with 7-Zip.
If that didn't work
These tools run in your browser. Your file is read and repaired on your own device and is never uploaded.
Broken Phone Backup File Extractor
Reads the header, decompresses as much as survives, walks the archive skipping damaged parts and gives you an ordinary ZIP with the app folders intact. It works on unencrypted backups and plain .tar files only; encrypted backups are refused. The files come out as stored (databases, preferences, media); it does not convert them into a phone restore.
Open Broken Phone Backup File ExtractorCommon questions
Can it open an encrypted backup?
No. Without the password the data can't be read by anyone, so the tool tells you the backup is encrypted rather than guessing.
Is my file uploaded anywhere?
No. The tool runs as a program inside your own browser, so the file is read and repaired on your device and never sent to a server.