...but just because you are inexperienced in removing rollers does not imply that you don't know the importance of using a screw driver with a proper fit. I have fixed frozen rollers in the past using WD-40ish stuff and 0000 steel wool on the rod and gently on the inside of the roller with good results. Not attempting to argue with any of the expert advice above, but fixing a frozen roller isn't rocket science or brain surgery (not sure why brain surgery is always used as an example, as the are plenty of other equally complicated and certainly more intellectually challenging tasks but so be it).