FTP
450 File Action Not Taken
Requested file action not taken. The file is unavailable due to being busy, locked by another process, or temporarily inaccessible.
When You See This Code
When you try to access a file that is locked by another user or process, or when the server temporarily cannot process the file.
How to Fix
Wait and retry the operation — the file may be locked by another transfer. If persistent, check server-side file locks and permissions.