Some setup will be necessary both on the WorkCenter and in your software. I will describe these steps and leave you with a link to Xerox to check as a reference:
On the WorkCenter 7335
1) In the Bypass tray, load the std. 10 envelopes width-wise with the side to be printed down, flaps tucked in and with flaps entering the printer first. Slide the guide to just touch the edges.
2) Touch <Change Settings> on the WC 7335 screen
3) Select "Envelope" from the "Paper Type" list
4) Select "No. 10 Env" from the "Paper Size" list
5) Select "Save"
6) Select "Confirm"
In your software:
As you did not specify your software, it is important to note that whatever application you are using, the following settings must agree with the steps above:
1) Feed method = Face down, Clockwise rotation
2) Feed from = Bypass
These options may be chosen in different ways depending on your software program.
You may review these setup steps for Word here:Xerox WC 7335 Print Size 10 Envelope