Jammed scanner Canon FB 630U

[David H]

My scanner arm has jammed a few times and always released when unplugged and plugged back again via the USB cable, but this time it's stayed put since yesterday. I read a gentle tap may release it, and fiddle with the lock button, but the arm is firmly at the front (I think it ought to stay at the back unless scanning). It is 12 years old but always worked perfectly although I have a new one if necessary it's far too big for the desk as a combo used for photo printing. I've also read if you undo all the screws to get the glass off and poke it with your finger it will do the same but I'd rather not myself.

Secondly it has also crashed my Adobe Photoshop Starter Edition and Picasa, neither of which will run once opened. I can always load new copies but may give a clue where the problem is. Any ideas?