Network Connections

Hi, i encounter this error when i restart my server. After i logon, it begins with the blank blue screen then have to wait around 5 to 10 mins then the desktop icons appears. But after the icons appear i can’t access to the web, *also the network connection icon @ the task bar is missing. I tried opeping network connection, it hangs there. i tried using ‘ping’ command to ping to websites it has a reply, but i cant access to the web. As this server host applications, although when i ping the gateway and dns i recieve a reply. But user just can’t log on to the applications. Anybody knows what happen? Please help me.

Thanks!