I'm not sure about outlook, but if you're talking about outlook express, the path to go to looks like this:
C:\Documents and Settings\Administrator(or username)\Local Settings\Application Data\Identities\{########-####-####-####-############}\Microsoft\Outlook Express\
Just copy all the *.dbx files in the directory to a backup location. When you reinstall windows, create your internet connection as normal, but when it asks you to set up the mail account, put in an INCORRECT server for the incoming mail server. After you do this, load up outlook express, it should give an error about not being able to get your new mail. Ignore this, go to settings and then put in the correct mail server address. Close outlook express (without checking for new mail) and then NUKE the contents of the new directory in (the same location as the one mentioned before). Copy the previously backed up files to that location (it should be empty), load up outlook express, and boom--you're back to the way you were before. Now for the address book...just copy the (yourusernamehere).wab file from
C:\Documents and Settings\Administrator\Application Data\Microsoft\Address Book
to a backup location, and copy it back over after you have set up outlook express. The reason you do all that crap with using an incorrect server name, etc, is because outlook express makes that previously mentioned (long) directory only after it loads up the first time. If you use an incorrect mail server address, it will check for new mail, and if you do have new mail, the backup restore process I mentioned will overwrite the new mail. I'm sure there's a way to append to the newly created mail list if you didn't want to do it my way, but I find this way works the easiest and also keeps me out of those damned micro$oft wizards. Please note that I never use the address book and have thus never tried backing it up as such, although I'm almost 100% sure it will work. The mail backup is 100% guaranteed to work, though. Have fun!
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