A. Well, it may be a bug. But I’d guess your mouse needs some obedience training. First, try using the F8 key that many of us once used in WordPerfect to control the highlighting of text. Place your cursor where you want to start highlighting and press F8 once.
Notice that the EXT mode indicator, situated at the bottom of the screen, is activated. Then, using either your mouse or the keyboard, move to where you want the block to end, and do what you want to do: copy (Ctrl+C), cut (Ctrl+X) or paste (Ctrl+V). When finished, click on Esc to deactivate EXT. In Excel, EXT is canceled by pressing on F8 again.
If that doesn’t solve your problem, the next option is to train your runaway mouse. Click on the Start button, then Settings and Control Panel and then Mouse . Now click on the Wheel tab (see screenshot above). Notice you can control the number of text lines (or cells) that will scroll for each notch movement of the wheel. You also have the option of moving a full screen at a time.
While you’re in the Mouse Properties screen, check out all the other tabs and fine-tune the mouse controls to your liking. You may even want to change the cursor icon or, if you’re left-handed, switch the mouse buttons. You also can adjust the double-click speed and turn on a lock so you don’t have to hold down the mouse button when you click and drag (see screenshot at left).