One of my clients found herself in a merry pickle when she was using Word. Suddenly instead of her normal screen, she had the one below:

She tried Control Alt Delete; she tried restarting – nothing seemed to work.
The solution: she had inadvertently pressed this icon which is the document map icon:

All she had to do to restore her normal window was click on the icon again.
Warnings:
Keep your antivirus program up to date – there are some very nasty viruses around.
Run maintenance wizard in safe mode every couple of months to clean up your hard drive.
Make sure when you buy new software or have it installed that you have the original of the software.
Keep all product codes in case you have to reinstall the software.
Thank you to all those who have bought my book and who have let me know how useful they have found it.
Cheers,
Deirdree