Do a System Restore to a date earlier than when you first noticed the icons were missing.
If that doesn't work - go for an on-line AV scan:
http://housecall.trendmicro.com/
Help! I have missing items at my desktop, when I click on START, things like RUN, LOG OFF, SHUT DOWN, are missing. I can't get to my CONTROL Panel from anywhere. When I try I get a message that says "This command has been cancelled due to restrictions in effect on this computer. Contact System Administrator". The only thing on the drop down beside "settings" is taskbar and Start Menu. I have no idea what's happened!
Could I have set something by mistake?

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