Clive,
> What should I do? By the way my PC has been in Suspend mode for some time.
> I plan to change my gmail password first off.
Gmail password has probably been guessed and that is the most likely source. 
Check your account thoroughly to make sure non of the phone numbers or 
security questions for it have been changed. You may want to contact 
Google/Gmail security team - though I don't know how much response you'll get 
from them - it's probably quite common and real problem for them.
Happened to my father twice with Hotmail and some someone I know with 
BT/Yahoo. It seems to be alarmingly common.
-- 
Adam Trickett
Overton, HANTS, UK
To send one out of office message may be considered
unfortunate, but to send two looks like cluelessness.
    -- Simon Cozens
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