Are you sure also that you execute the miner as admin ?
I don't think he needs to execute the miner as an admin. The only miner that needs this (that I'm aware of) is xmr-stak-cpu (and that's only for higher hashrate and not mandatory). Anything else, including the claymore ethereum miner he's using, doesn't require administrative privileges.
Okay, doesn't hurt to try, but you are right probably not the issue.