Thank you Bach-man; worked great.

I was given a Bachmann DCC Digital Commander Set as a gift, and I'm having difficulty programming either of the two engines to a different address.  Otherwise, both locomotives seem to work fine.  Both locomotives run smoothly forward and backward responding nicely to throttle adjustments.  Unfortunately, I cannot run both at the same time since both are assigned to address 3 and I'm unable to change either one.  I have gone through the steps in programming a locomotive to a specific address several times but to no avail.  With only one engine on the track, I run it for a short distance then simultaneously press '3' and 'stop', and release them at the same time.  The programming light under the stop button blinks, but then neither locomotive responds to a different address.  Am I missing a step, or am I doing something wrong?

Any help is greatly appreciated.  Thank you.