The ability to print envelopes often has more to do with the printer than
Access. If your printer can handle 30 envelopes, just create a report and set
the paper size to that of the envelop.
I often use two other options.
1. Print out labels to stick on the envelop. Cheap and simple. There is a
label wizard to help.
2. Use 'window' envelopes. Set up the report or mail merge to Word in such a
way that the recipient's address shows in the plastic window when the paper
is properly folded. This can look very professional plus solves the problem
of having the right letter for the address either printed on the envelop or
printed on the label.