I've got a 4250 and I need (according to documentation) a product enablement key to enable fax server. I don't see it as disable...i plan just dont see it. So according to the WorkCentre 4250/4260 Version 4.0 Use guide not all features are enable. You plug in the enablement key and pick the items you want enabled. Each 4250 comes with a Product Enablement Key in a plastic Tube. Seems noone can find this. Also is each key tied to a specific printer by serial number...etc.
It was/is a number and letters code printed on the documentation that came with the printer, if it was thrown away then the option is gone and would need to be purchased separately through Xerox or a 3rd party reseller.
Xerox hasen't sold the 4250 in over a year (February 2016) so you would probably need to call as nothing will be on Xerox.com
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