Does a BMW electronic control unit (engine computer) need to be programmed?

Had issues starting my car so I borrowed an ecu from my friend that is a mechanic %26amp; it started up fine without any programming. I bought one online %26amp; popped it in %26amp; its not working. I contacted the seller %26amp; they said that I need to take it to the dealership to get it programmed. I called bmw %26amp; they said they same thing %26amp; that they will charge me an hour of labor to get it done. Just wondering if it really needs to be programmed since the ecu that I borrowed works fine even though I didnt program it. Thanks.|||What is the year of your car? In most of the newer cars (except for the really old ones) BMW DME's (engine computer module) needs to be programmed before it can be used when new. When bought already used it is already programmed but it can not be transferred to another car without transferring the EWS (antitheft module) also, that is except for the older cars.|||Yes, it DOES need to be programmed!|||It must be programmed to the car and in many cases, it cannot be reprogrammed after it has been installed. Most used modules will never work with any other car than the one it was first programmed in.