W. Va. Code § 56-3-9: Service in other county; return.

A sheriff or other officer may transmit by mail (the postage thereon being prepaid) any process or order which came to his hands from beyond his county, with his return thereon, in an envelope or cover properly addressed to the officer to whom or whose office such return ought to be made; and the receipt taken at the time from the postmaster, his deputy or clerk, certified as aforesaid, shall be evidence that the process or order, and return, were transmitted as aforesaid.