New DNS settings from router not pushed to all stations

New DNS settings from router not pushed to all stations

After updating the static DNS settings on our Cisco WRVS4400N router,
approx 1/3 of stations did not receive the new DNS settings. On the
stations that did not receive the new settings,
ipconfig /all
still shows the old DNS settings.
Network has approx 15 workstations. Mix is half/half Windows 7 Home
Premium / Windows 7 Professional.
There is no relationship between the Windows version and which
workstations are not getting the new DNS settings. (Stations that received
the new settings did so immediately, without rebooting)
There is no relationship between stations rebooting and receiving the new
DNS settings.
I have tried:
rebooting
ipconfig /flushdns
ipconfig /release and then /renew -- however, received message to the
effect that "no adapters are in a state to respond" to those commands.
Suggestions? Ideas? Insights? Things to try?