After working on a word document, after saving it we try to open it again, but the content is corrupted. things are removed and extra symbols are added?

This is not the normal behaviour, as I'm sure you'd know. What is being added/deleted? Can you attach a document to a post with some representative data (delete anything sensitive)? You do this via the paperclip symbol on the 'Go Advanced' tab at the bottom of this screen.

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Cheers,
Paul Edstein
[Fmr MS MVP - Word]

Do you make image backups of your complete system? (everyone should)
If you do, and depending on the imaging program that you use, you can mount the previous image, and recover an earlier version of your Word document.

Also look here: http://social.technet.microsoft.com/...um=officeitpro