Problem Description: I would try and open Firefox while connected to the network, it'd take maybe 3 minutes to actually open, and then it would never load a page. When I tried viewing a webpage on IE, it gave me an error that the DNS Server could not be reached. I ran the diagnostics tool, and it returned an error: "Cannot communicate with primary DNS server. Network Diagnostics pinged the server, but did not receive a response."
Briefly: Modem connected with Internet, first few minutes browsing done properly, after that unable to browse, if pinged no DNS server found.
Probable Solution - Reset Log Files: Open up a command prompt (Start > All Programs >Accessories > alternate click on Command Prompt > select "Run as Administrator"
Type the bolded commands into the command prompt window:
Reset WINSOCK entries: netsh winsock reset catalog
Reset IPv4 TCP/IP: netsh int ipv4 reset reset.log
Reset IPv6 TCP/IP stack: netsh int ipv6 reset reset.log
When finished reboot
Probable Solution - Disable the IP Helper service: Open services.msc by clicking Start> Run. Scroll down to the IP Helper service, right click on it and select Properties in the dropdown box that says "Automatic" or "Manual", set it to Disabled and then click on "Apply". Then click on "Stop" to stop the service from running in the current session. Click OK to exit the dialog.
Probable Solution - Disable IPv6: Open ncpa.cpl by clicking Start> Run. Right click on each network connection and select "Properties" to remove the checkmark from the box next to "Internet Protocol Version 6 (TCP/IPv6) and theb click OK to exit the dialog. Note: For Windows 7, Vista, etc.
Probable Solution - Disable the DHCP Broadcast Flag: By following below statements,
1. Hold the Windows key and type R, enter regedit and press Enter.
2. Locate and then click the following registry subkey:
4. In this registry path, click the (GUID) subkey to be updated.
5. If the key DhcpConnForceBroadcastFlag does not exist, use the Edit menu, point to New, and then click DWORD (32-bit) Value. In the New Value #1 box, type DhcpConnForceBroadcastFlag, and then press ENTER. If the key exists, skip this step.
6. Right-click DhcpConnForceBroadcastFlag, and then click Modify.
7. In the Value data box, type 0, and then click OK.
8. Close Registry Editor.
NOTE: You should do this for each and every GUID subkey.
NOTE2: (GUID) is a mnemonic for the individual subkeys, the actual text "GUID" does not appaer.