Due to some changes in the network stack, Microsoft® Windows XP Service Pack 2 (and others) may not play well if you use 127.0.0.1 as the DNS address. If you experience excessive CPU usage from the TreeWalk process, try the following:

• Uninstall TreeWalk, reboot
• To manually install the Microsoft Loopback adapter in Windows XP, follow these steps from the Microsoft site (use the links provided further below for Windows 2000 instructions):
• 1. Click Start, and then click Control Panel.
  2. If you are in Classic view, click Switch to Category View under Control Panel in the left pane.
  3. Double-click Printers and Other Hardware, and then click Next.
  4. Under See Also in the left pane, click Add Hardware,and then click Next.
  5. Click Yes, I have already connected the hardware, and then click Next.
  6. At the bottom of the list, click Add a new hardware device, and then click Next.
  7. Click Install the hardware that I manually select from a list, and then click Next.
  8. Click Network adapters, and then click Next.
  9. In the Manufacturer box, click Microsoft.
  10. In the Network Adapter box, click Microsoft Loopback Adapter, and then click Next.
  11. Click Finish.
• Open the newly installed adapter properties and setup its TCP settings using a subnet different from any other subnet you're using and save the new settings (a good choice may be using 172.31.254.254 with a subnet mask of 255.255.255.0)
• Now proceed installing TreeWalk with all adapters enabled and once the setup completes, reboot the machine, then edit your TCP settings and replace the DNS address from 127.0.0.1 to the address you used for your loopback adapter (e.g. 172.31.254.254)
• Reboot again (if the system requests it) and you'll be up and running
• 
  An alternative to the above may be to apply this XP patch listed at the Microsoft Knowledge Base.
• Use the following Microsoft link to install the loopback adapter for Windows 2000 or preview this article in our own "Tweaks and Repairs" section (originally compiled by the late Ted Quantrill for his "Tip Quarry" collection).
• We provide a page of recommendations on how to configure TCP/IP Properties after you've created the loopback adapter.

Uninstalling: to remove the Microsoft Loopback Adapter, right-click any "My Computer" icon, select "Properties", open the "Hardware" tab, press the "Device Manager" button, scroll to and expand "Network adapters", right-click "Microsoft Loopback Adapter" and select "Uninstall". Reverse any earlier changes to relevant adapters if any were required and reboot if your system requests a restart. Check for Internet connectivity.

• Relevent topics:
• Microsoft Loopback Adapter configurations (TreeWalk site)
• How To Install Microsoft Loopback Adapter (TreeWalk site)
• MSKB 884020 (Microsoft Support Knowledge Base article "Programs that connect to IP addresses that are in the loopback address range may not work as you expect in Windows XP Service Pack 2".)
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