Can't open any tabs

Please help! I am unable to open any tabs in the mixer rack and inspector panel in the sequencer window. Clicking on anything like inserts, sends etc. does nothing. It seems like a strange graphics issue.
Everything was working fine the previous time I used cubase, I tried restarting cubase (7.07, 64 bit - Windows 8.1, 64 bit) and my pc, but the problem still persists.
Any suggestions will be greatly appreciated.

Hi Markal,

please restart your computer by clicking on “Settings -> Power -> Restart”. This will get things back to normal.

Please note: Do not turn it off and then on again, this won’t make any difference. You have to use the “Restart” option to get things sorted.

Regards

Thank you very much Luis, I greatly appreciate your assistance.