If OpenExtract shows an error, look for its words below. Each problem says what the app shows and what to do about it. On a computer, Ctrl+F (Cmd+F on a Mac) finds the words fast.
What you see: pymobiledevice3 is not installed. Run: pip install pymobiledevice3
Fixed in OpenExtract 0.15.1. Get the latest version.
OpenExtract 0.15.0 can't make backups: a part it needs was left out when this version was built, so every backup stops at once and says pymobiledevice3 is not installed. Installing pymobiledevice3 yourself won't help, because OpenExtract uses its own copy. OpenExtract 0.15.1 fixes it: install the latest version from openextract.app, then try the backup again.
What you see: Your iPhone is too full to make a backup
Your iPhone itself is too full to make a backup, however much space the computer or drive has: it needs some free space of its own to prepare one. (OpenExtract 0.10.1 and earlier said the drive was too small instead.) On the iPhone, open Settings > General > iPhone Storage, delete or offload what you don't need, then try the backup again.
What you see: Not enough free space for this backup
The drive you chose doesn't have room for the backup. A backup can need much more space than your iPhone shows as used, because the iPhone counts some files more than once. Choose a folder on a drive with more free space, such as an external drive, or free up space on this one, then try again.
What you see: No such value.
Fixed in OpenExtract 0.10.2. Get the latest version.
OpenExtract 0.10.1 and earlier can't make an encrypted backup of an iPhone that has never made one. Install the latest version from openextract.app. If you can't update yet, turn off "Encrypt backup" and try again; an unencrypted backup leaves out some data, such as saved passwords and Health data.
What you see: Your iPhone couldn't send some of its files or Multiple errors uploading files (MBErrorDomain/104)
The iPhone couldn't read or send some of its files during the backup. Restart your iPhone, plug it back in, unlock it, then try the backup again.
What you see: unfinished backup of this iPhone from an earlier try or Error reading backup manifest properties (MBErrorDomain/205)
An earlier backup into this folder stopped partway, and the iPhone can't continue it. Choose a new, empty folder and try again. Once the new backup has finished, you can delete the unfinished one.
What you see: OpenExtract wasn't allowed to change a file in the backup folder or [WinError 5] Access is denied
Another program may be using the backup folder: OneDrive and other cloud folders, and antivirus software, can hold on to files while they work. Choose a new, empty folder that isn't in OneDrive or another synced folder, close any window showing the old one, then try again.
What you see: Sidecar call timed out: backup.start
Fixed in OpenExtract 0.13.0. Get the latest version.
OpenExtract 0.12.0 and earlier stop waiting for a backup after 2 hours, even while it's still copying, so a big backup stops partway. OpenExtract 0.13.0 fixes it: install the latest version from openextract.app, then try the backup again. It now gives up only if the iPhone sends nothing for 2 hours.
What you see: Your iPhone was disconnected before the backup finished or The connection to your iPhone dropped partway through the backup or Your computer went to sleep during the backup or The connection to your iPhone was terminated unexpectedly
A backup can take hours, and the iPhone drops off if the computer goes to sleep or the USB connection is interrupted, even while it stays plugged in. OpenExtract 0.13.0 and later keep the computer awake during a backup, so if you have an older version, install the latest from openextract.app first. Keep the computer plugged in, keep a laptop's lid open, and don't let it sleep until the backup finishes. Plug the iPhone straight into the computer, not through a hub, dock or monitor, and try another USB port if it keeps happening. Then try the backup again.
What you see: OpenExtract needs Apple Devices, Apple's free iPhone app for Windows or Cannot connect to Apple Mobile Device Service
To find or back up an iPhone, Windows needs Apple Devices, Apple's free app (iTunes works too). Get Apple Devices from the Microsoft Store, open it once, then restart your PC. Then plug in your iPhone, unlock it, tap Trust if it asks, and click Refresh in OpenExtract. You don't need it to open backups you already have.
What you see: Sidecar exited with code 1 or Python sidecar is not running
Fixed in OpenExtract 0.13.0. Get the latest version.
OpenExtract 0.12.0 stops working a few moments after it opens a backup made by iOS 6, when it reads the backup's photos. After that, everything says "Sidecar exited with code 1" or "Python sidecar is not running". Reinstalling 0.12.0 won't help. OpenExtract 0.13.0 fixes it: install the latest version from openextract.app, then open the backup again.
What you see: Incorrect password. Please try again.
An encrypted backup uses the password you chose for backups in Finder or iTunes. It isn't your iPhone passcode or your Apple Account password. If you can't remember it, it can't be recovered, but you can remove it on the iPhone: Settings > General > Transfer or Reset iPhone > Reset > Reset All Settings. That keeps your data but resets settings such as Wi-Fi passwords and wallpaper. Then make a new encrypted backup with a new password.
What you see: macOS is blocking OpenExtract from reading or Operation not permitted
macOS keeps iPhone backups in a protected folder. Open System Settings > Privacy & Security > Full Disk Access, turn on OpenExtract, then quit and reopen OpenExtract.
What you see: No iPhone backups found in
Choose the folder that holds your backups, not one backup inside it. If a backup you were making with OpenExtract didn't finish, there's nothing to open yet: make the backup again first. On a Mac it's Library/Application Support/MobileSync/Backup in your user folder. On Windows it's usually Apple/MobileSync/Backup in your user folder, or AppData/Roaming/Apple Computer/MobileSync/Backup.
What you see: Python sidecar is not running
Quit OpenExtract and open it again. If it still can't open backups, download the latest version from openextract.app and install it over this one. On Windows, security software (Windows Security, Smart App Control or an antivirus) can stop part of OpenExtract from running: check it for a recent alert about OpenExtract.
What you see: Sidecar call timed out: export_photos
Fixed in OpenExtract 0.11.0. Get the latest version.
OpenExtract 0.10.2 and earlier stop waiting for a save after 5 minutes. That isn't long enough for a big photo library, especially from an encrypted backup. Install the latest version from openextract.app, which waits much longer and shows how far a save has got. If you can't update yet, the files usually go on saving anyway: open the folder you chose and wait until new files stop appearing, then quit and reopen OpenExtract before you browse again.
Tell us from the app: click Report this problem next to the error, or open Settings and choose Report a problem or send feedback. You don't need an account. The report includes what went wrong, but never your messages, photos or other backup content, and you can read it before you send it. You'll get a reference number, and OpenExtract tells you in the app once the problem is fixed.
You can also open an issue on GitHub, where anyone can see it.