JP1 Remotes

My guess is, you just need to upload the right image for the extender that you had loaded. I understand that you don't know what that is, so best I can suggest is that you store an RMIR file for each possibility, then load them one at a time to see if it lets you deactivate the extender.

Capn,
Are you able to download what you now have?
If so, the extender version is in 2 bytes at $07FE, at least for version2 of the extender. Take a peek at the Raw data.

Edit: Ditto for version 302. Those two bytes are 03 02, For my 211 they're 02 0B.