TWRP createTarFork() error 255 when backing up data I have installed FreedomOS on my OnePlus 5. I'm not sure if this is related to FreedomOS, but when I try to make a backup in TWRP with data, system, and boot, it has an error with createTarFork() shortly after it gets to backing up data. It also says 'read only filesystem' when I try to open Terminal from Advanced and run 'cd /data/media/0/TWRP/BACKUPS/bad7d639 &amp;&amp; rm -rf backup-name'. What can I do to fix this and why is this happening?
For me, the error was related to the I/O or file corruption issue.

To find what has happened, browse to the backup location (usually /external_sd/TWRP/BACKUPS/backupfolder) and find the recovery.log file. Open the file, and at the bottom lines, read what folder caused backup failed.

Delete the corrupted folders using TWRP File Manager, delete the old backup folder, and try to do a backup again. Consider that this may occur for different folders, so you need to read the log file every time.