Mouse pointer stuck in an unusual selection mode

[GwydionM]

While trying to select a block of text to cut-and-paste, I must have somehow put the mouse into an odd mode. Instead of starting from where I clicked, it would start from the top of the document and continue down to wherever I had clicked. This applied to the browser (IE6), to Word and to Notepad. It even managed to 'cleverly' remember this setting through a Restart: only shutting down and beginning again cured this.

The answer is probably something absurdly simple, but I can't find it.

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An old man who lives in the UK

 

[linney]

If the problem is fixed, it may have been one of those unknown mysterious glitches that computers are famous for?

As it occurred across different Applications all you can do is look at the Mouse itself, and any settings for the Mouse in the Control Panel.