Canonical: https://rom-weaver.com/docs/fix-permission-errors # Fix a permission error Get past a `Permission denied` error from the CLI. The message itself carries what you need: what was refused, who owns it, and who asked - [File permissions]() explains the format and when the checks run. ```text error: i/o error: cannot open `/roms/game.iso`: Permission denied (os error 13) (`/roms/game.iso` is mode 0600 owned by 0:0; this process runs as 1000:1000) ``` Match your situation: - **Reading someone else's files.** `sudo chown` them, add yourself to the owning group, or copy them somewhere you own. - **Writing to a read-only location.** Point `--output` at a directory you own. rom-weaver creates missing output directories but never changes permissions on an existing one. - **Output files owned by the wrong user.** New files inherit your identity and umask; rom-weaver does not copy the source file's mode. - **Inside a container.** The message adds a container hint, because the usual cause is a uid mismatch against a bind mount. Re-run with `--user "$(id -u):$(id -g)"` as shown in [Run in Docker]().