I have a Linksys WRT160N which, for no apparent reason, keeps resetting itself so that the SSIN and security settings revert back to the factory defaults. The firmware is current so I'm not sure what's going on.
It's broken and needs to be exchanged for one that works.
Bad firmware. Try upgrading to the latest firmware.
Hack attack: Did you set a new admin password? Someone might be playing games with your router. Disable remote administration at:
Power glitches. The unity might be sensitive to power line induced
Go to the Administration -> Log page and enable logging. See if there are any clues in the log files when it resets, especially the security log. If it's totally blank, then it's likely a reset to defaults.
Check that the reset button isn't defective. It should have a firm clicking sound.
Also ask in the Linksys Forums:
and search for your router model number. I got quite a large number of hits for "WRT160N reset" (in the advanced search), but nothing specific to your problem.
It's probably under warranty, so you might consider calling Linksys support.