How do you re programme a key fob om Mercedes 270 ML?

Bring all keys to dealer. When re-programming, the dealer's equipment will change the code that is relayed from key to immobilizer in car, thus the reason you need to bring all keys to the dealership.

According to two different Mercedes Dealers. Sears imported Autos and Feldman Mercedes it is not allowed. All keys must be ordered from a dealer and programmed by the factory according to your VIN...

No

I had not used the 2nd key fob for my 2000 S500 for several years, so it lost its memory. I took it to the dealer and they wanted $500 to reprogram it! After doing some research on MB forums I found...

put the key in the ignition push the lock button on your keyfob, pull the key out while holding down the lock button and press the unlock button 5 times. Your key is now reset and ready for use this...