I have a 2006 mini cooper s hardtop. I was having key issues. So i went through the 2 different styles of programming that i could find. The one version worked perfectly for one key only. The other key will not do anything. I tried driving with it for about 3 hours thinking the battery was bad in it. Tried programming again and still nothing. Any ideas? Is the key battery bad so i just need another key?

 

Put in the key that will not program (assuming it is the keyless entry only) and go for a few LONG DRIVES....if the key sat unused, the battery might be very weak/dead...the 2005+ "refresh" cars batteries recharge when driven....
It is possible the battery is totally dead/not holding a charge.....
The you could either...
Get a new key....dealer only...
Or possibly buy a used junk key/eBay blank of the same style and move the battery....at one point somebody posted a source of batteries (had to get them mailed from Taiwan if I recall)....
Issues is the key is not made to be opened...so you will likely marr it or even destroy it.
So you could just keep it as a manual key.....as is.....
All this is a moot point if it will not START the car....that is a seperate RFID chip....only fix there is a new key.

 

it starts the car and works manually, just has no remote features.