Parked car in garage one night and went to drive it the next morning and the transmission would not engage. Goes into park and netural OK but not into any forward or reverse gear. Anyone out there with ideas???

There might be some clutch problem,have you already checked the gearbox?Or the mercedes benz fuel pump (http://www.eurobzparts.com/mercedes-benz-fuel-pump/) may not be functioning properly and fuel intake does not flow enough to get the car goin.

fOR ANY LOOKERS, THE TRANSMISSION FILTER WAS CLOGGED. IT IS A FAIRLY NEW, REBUILT ONE, ONLY 7000 MILES SINCE IT WAS WORKED ON. THE REBUILDER MUST NOT HAVE FLUSHED THE CASES OR PARTS OUT.