Adobe Digital editions won't start up anymore

My ADE won't start up anymore and before today it has always worked fine. When I click the program or start it up as administrator I get an error message saying that the program stopped working or sometimes none at all, it just won't start. I tried restarting my laptop and i reinstalled the program several times, but the same problem keeps popping up. My OS is Windows Vista. Do you know how to solve this problem?