TCP/IP not working in Windows XP/2003

Problem

In Windows XP/2003, TCP/IP is not working and traditional reset procedures using netsh int ip reset or netsh winsock reset fail to resolve it.

Unlike prior versions of Windows, TCP/IP cannot be easily removed and reinstalled to correct such problems.

Solution

Procedure is to enable uninstalling TCP/IP, uninstall TCP/IP, reboot, reinstall TCP/IP and reboot:

1. Click Start, Run, type Regedit and click OK.

2. Delete the following keys:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Winsock
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WinSock2

   Close Regedit.

3. Click Start, Run, type NOTEPAD %SystemRoot%\INF\nettcpip.inf and click OK.

   In Windows Vista and above, run this command from an elevated command-prompt. But first you must set the ownership of the INF folder to Administrators, then set Full Control to Administrators.

4. Under the section [MS_TCPIP.PrimaryInstall], change Characteristics = 0xA0 to Characteristics = 0x80.

   Close Notepad and save the file.

5. In Control Panel, open Network Connections, right-click Local Area Connection and click Properties.

6. In the Properties dialog, click Install, Protocol, Add, click Have Disk and enter C:\WINDOWS\INF.

7. Choose TCP/IP from the list.

   Note: This will bring you back to a properties screen, but now the Uninstall button is available.

8. Highlight TCP/IP and click Uninstall.

9. Reboot. (Note that a lot of services will fail on startup.)

10. In Control Panel, open Network Connections, right-click Local Area Connection and click Properties.

11. In the Properties dialog, click Install, Protocol, Add, click Have Disk and enter C:\WINDOWS\INF.

12. Choose TCP/IP from the list.

13. Reboot.

— Posted to NTBugTraq by Russell Tammany, Xponentia Inc.
13 August 2004