Use secure vaults to store PLC credentials.

For hardware UM passwords, Omron provides a legitimate method—but it is . Using CX-Programmer, you can perform an "All Memory Clear" operation. This erases the entire user program and its password, resetting the PLC to factory defaults. This does not recover the password; it deletes it along with the program. This is useful if you own the code but have lost the ability to upload it, provided you have a backup file.

: For legacy models like the CPM2A, you may need to ship the unit to an authorized service center for manual clearing. Common Recovery & Reset Methods