Dear Sir,
There is a network that contain zywall usg-100 router(192.168.1.5), AD 2008r2 with dhcp (192.168.1.17), Client PC win7 pro(192.168.1.120)....
in fact, there are some win7 pro also get this problem...total about 60-70 client.
I keep AD server gateway blank as I don't allow the AD Server access internet....
ISP provide dns
218.102.23.228
210.87.253.13
I also set 8.8.8.8 and 8.8.4.4 to DNS
It happen suddenly.
Client PC can ping server and router.but it can not access internet....
tracert and ping yahoo.com but also failed....
nslookup yahoo.com and the dns server is router(192.168.1.5)...it is scucess... but still can not ping yahoo.com
I process ipconfig /release and ipconfig /new it is OK again....
but it also happen suddenly again after 1-3 hours
please advise....