I am trying to logon a user to the domain and I get an error right away
saying the domain could not be found (works fine wired, though).  If I logon
to the domain as another user, it works fine.  Both of the users have
accounts on the laptop.
Any idea of what could be wrong with that one user?

Check that the domain controller is FIRST in the list of DNS servers for the
wireless connection. IPCONFIG /ALL will give this info.

Wireeless routers are generally DHCP, and they tend to make themselves the
DNS proxy, so this might well be the trouble-area.

It may also be worth issuing NBTSTAT -R to clear any remembered
hostname-info from the wired connection, which will have had a different IP
address. (Unusually for a Windows command, this IS case-sensitive)

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