Hi,
a) From when are you facing this issue?
b) Was it working earlier?
c) Did you update all the drivers on your computer?
Check to see if you have a F Lock Key in the upper right-hand side of your Keyboard.
Try with another keyboard.
I would suggest you to download and run the HotFix in the below link to resolve the issue with the function keys and the keyboard shortcuts:
You need to click on the "View and request hotfix downloads" on the top of the page and fill up the info and then you will recive the hotfix and then install it and check
http://support.microsoft.com/kb/975741
Thanks and Regards:
I. Suuresh Kumar- Microsoft Support.
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