Microsoft Word not responding?

Having read your question and additional details I have to ask, as you say it is very slow, although you are Vista, did you install this on your computer as an update or did you buy new computer with Vista on. If it were an update, possibly you do not have enough RAM and/or too many programs running at start up. Someone has suggested a Repair which is a good idea but the fact that it stops responding and is slow does seem to indicate lack of RAM. Also I am assuming this is full version, not trial because with trial version, you are limited. When you say you left Word open and came back and it was blank, it would have automatically gone into sleep mode and all you needed to have done would have been to touch a key and it should have come back. Possibly if you can't rectify through a repair and you do have at least 2gb of RAM, and it is your full version with CD, I would reinstall

Since this only happens with one document, it appears that this document is corrupt. It is very difficult to say how it became corrupt corrupt. Highlight everything but the last word in the document (Click at the beginning of the document and press Shift-click near the end of the document and everything in between will be selected) and press Ctrl-C. Press Ctrl-N to open a new document, and press Ctrl-V to paste what is on the clipboard to the new document. Does this new document have the same behavior as the first document? If it does, this time select the first half of the document and paste it to a new document. What I am trying to do here is find out where the corruption in the document is. Keep pasting more of the original document until you find out where the corruption is. Many times the corruption is in the last ¶ in the document. If corruption in this document is the problem, uninstalling Word and reinstalling it will have no effect. EDIT: Do not use any so called optimizer or registry editor (such as RegInOut). Many are too aggressive and will do more harm than good. The only one I would use is the one in CCleaner. You will never see an evaluation of a registry cleaner except those done by the company marketing this software. This is because, in spite of the speedup in your system that they promise, they have almost no effect.

You can try putting your Office install disc back in and doing a Repair. That may work if the problem is due to a corrupt file. Or just uninstall and reinstall. If the problem is with Office then that should fix it. Otherwise the problem may be with the OS.

Do any other applications give you these hangups? How old is the machine? Which OS? Which version of Office?