Hi Pirkka,
Try this to check what users are on your system:
Press WinKey+R(that's the MS-LOGOkey+R) to get the Run-Box.
Type this: cmd to start a CommandPrompt
In the CommandPrompt, type this:
net users
to see a full list of users on your system.
There will be a Administrator account, Support_XXXXXXXX, Guest, HelpAssistant,...
Some of them you may not see normally, but these are Microsoft HelpDesk ones.
To check for the last time any of them logged on:
net user USERNAME
Support_XXXXXXXX (XXX means some number) is usually the Microsoft Remote HelpDesk. I'm not sure whether just 'Support' is a normal one.
If this is a hacker, then I suggest you post your question on the Security & Virus forum (check the left of this page). The experts will have better advice on what steps to take to kick the baddie off your system.
HTH-Happy NewYear!!
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