How do I get rid of “File Permission Error” on MS Word?

Hello,
I have a big problem. I am unable to save files on Word. I am using Windows XP. It says some file permission error. What can I do to solve this error?
This machine is my home PC. I create and save word documents as I am a writer. I never got such error earlier. My machine is a Dell Latitude one with Windows XP. This is the error I get when I try to save word document.
“word cannot complete save due to a file permission error (C:… name of document .docx)”. Sometimes this message is followed by “saving auto recovery file is postponed for {file name}”.
I tried using a different name too, anyhow it saves a blank word document except my data.
If you want any more details on this case I can provide them, but I think these are enough for now.
Please give me your help to fix this error.
Thanks a lot everybody.
