Thanks for quick reply, but the reply from Pondus do not apply.
I should have mentioned first time that I am using Office 97.
Anyway, I am enclosing a screenshot. In the Office file catalog winword.exe is missing.
Why has this happened when I encountered this problem with AVAST?
What shall I do to get Word working again? Simplest might be to uninstall the whole Office package and reinstall it?
? (if it not hangs up somewhere because there is an error in it)