So I have a significant amount of phone numbers in my address book in
(xxx) xxx-xxxx or xxx-xxx-xxxx format... when I look up Fax numbers in
the Address Book though, only the ones in "+1 (xxx) xxx-xxxx" format
seem to be recognized.

Now I can go through and click the button beside each number and Outlook
will automatically change them to this format... but that could get
extremely time-consuming with two or three numbers per contact for
several dozen contacts.

Is there some way to effect this change globally?