Windows XP Pro and Control Button

[Guest]

My laptop computer is not internet linked and runs Windows XP Pro, and is
used primarily for photographic files. So normally when running software,
(eg ACDSee & Windows Explorer) you can use the control button and the
keyboard and left click on the mouse to select multiple items. For some
reason on the laptop, this ability has ceased. Left mouse click and control
key will only select one item.
No doubt I have altered some function somewhere.
Can someone help me to restore the normal function please>

 

[Dave B.]

Shift selects multiple item, ctrl selects or unselects 1 item at a time.

--