a door lock may be the problem
simple to change, by peeling the door seal back , undoing the two screws and removng the lock
however , commonly, it could be the spring behind the handle, and thats worth checking
quick way to check would be to close the door, start a program and when it doesnt start, push back on the handle on the inside of the dorr, if the then works, its the spring rather than the lock
that is of course, uless the brushes have worn down, and its blown the board, but thats not so common
hope this helps