It started suddenly when I was trying to trim a photo in MS Paint. The mouse wouldn't drag the edge of the photo. The drag and drop problem also happens trying to play Microsoft Solitaire, and sometimes I can't move down a Web page if there is a scroll bar at the side. This seems to be an intermittent problem since sometimes the mouse works fine for a while, then "acts up", then it's fine again for a while. My system is using Windows 7 - 64 bit with a Logitech M100 optical wired mouse (about 4 years old). The cursor moves around okay, just seems to be the drag and drop function is getting finicky.
I tried cleaning around the outside of the clicker and dusting the bottom yesterday. Worked for a while, now it's doing it again, plus sometimes seems to "double click" when I press the left button. I even tried to "switch" the left and right clickers. That worked, but it is awkward for me to use that way. I also tried to update the mouse driver, but it said I have the best driver for it already.
I have no other mouse to swap out to test. I am trying to work around having the trouble and expense of having to go to a big box store 15 miles away to get a new one, if that is indeed the problem. I hesitate to take it apart since, with my skill and manual dexterity, am more likely to do more damage - better an intermittent working mouse than one that doesn't work at all. Is it more likely a problem with the mouse itself, a software issue or a virus? Will I just have to bite the bullet ad spring for a new mouse? Any other advice?