[TYPO3-english] RTE Disappeared?

[Scotty C]

Hi everyone,

A client has been running TYPO3 4.2.6 for years without a single problem. They recently contacted me to say their RTE (rte_plus) has disappeared from every content element in the backend and has been replaced by code. Also, there's no "disable RTE" checkbox. I can confirm this, and when I tried to remove it and replace it with HTMLarea, not even it will appear either! I checked the install tool and the RTE is enabled. Does anybody know what could possibly cause this mysterious issue?

Thanks,
-Scott.