Won’t happen to many of you, but here’s what to do if you suddenly find that you can’t drag and drop stuff in Windows XP.
First off, don’t panic. There’s lots of pages out there suggesting you have a virus. Not impossible, but unlikely.
Second, check that you haven’t got your escape key stuck. Do this either physically—something may be wedging it down—or else virtually—a program may have set it as on. This has happened to lots of people, if this post is anything to go by.
If that doesn’t work for you, try this.
What you’re going to do is change your registry, so back it up first.
Open the files inside the Zip.
The one you need is the dragndropx.reg.
Once you’re backed up, double click on it, and select yes from the resulting dialog:
Your registry should now be fixed.
Try dragging something—an icon, a file, some text—and you should be good to go.
(Note: I have a feeling this problem is caused by overzealous registry cleaners.)
If you’re still having problems, you may have something more serious: Run a good virus scan as your next step. If there’s still a problem, then it could be your mouse driver. Here’s some more (mostly inconclusive) chat about this.