I'm not sure why either it does it either Mitch. Just letting you know that
I've experienced it too - so you don't start to worry about your mouse or
your sanity.

I thought it might happen when you scroll and hold down a certain key (Alt,
Shift etc.) - which would be quite a useful feature - but unfortunately
that's not it!

Cheers,
Peter

" wrote:

Why does the wheel on my mouse sometimes, apparently randomly, scroll
left-right instead of up-down?