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Tools
Letters and Mailings
Envelopes and Labels
Select the Envelope tab
Enter your return address in the correct field
Select add to document

Go to File, Print, enter quantity of 50 & voilà!

It's not easy to do what's called an "overbar". You have to actually insert an "equation" field. If you are interested, here's how:

1. Fire up MS Word

2. Go to 'Insert' on the menu bar.
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