I just had the loss of ")" again, so turned on NirSoft's
KeyBoardStateView.

It showed exactly the same keypresses for "(" (shift-9) as for ")"
(shift-0), other than of course one had the 9 key and one the 0 key. But
I did notice that all the time it showed left Ctrl as pressed. Weird
thing is that actually tapping left ctrl had an effect (for example: I
have the Windows built-in utility on that draws circles round the mouse
cursor to help you find it if you tap either ctrl key, and tapping the
left [or right] ctrl key still makes the rings appear), so it doesn't
seem that the key is _actually_ stuck.

Tapping the left ctrl key a few times eventually made its "pressedness"
disappear from KeyBoardStateView - and hey presto, I could then type ")"
again!

It's still a puzzle: even if there _is_ a problem with the left ctrl
key, why should it stop me typing ")" - but leave me able to type "(",
"*", or any capital letter? [To recap: when this does cut in, I can
still type a zero, just shift-zero has no effect.] But at least I _may_
have a way of getting round it (other than cutting and pasting ")"s!).
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

The thing about smut is it harms no one and it's rarely cruel. Besides, it's a
gleeful rejection of the dreary and the "correct".
- Alison Graham, RT 2014/10/25-31