Last Updated: November 15, 2003

Well here we are, the moment we have all been waiting for. The PDC has finally arrived, and with it so has Longhorn Pre-Beta build 4051. There are many new things in this build that are worth checking out as well as a few disappointments we'd like to express. The main goal of this tweak guide is to get 4051 running in a way that it could possibly be suitable for day-to-day use. Well this is a tweak guide isn't it? Lets get tweaking!

Longhorn 4051 System Requirements

WinFS - What is it and how does it work?

Components Of the Sidebar

This is one of the disappointments of build 4051 if you ask me. Microsoft seriously downsized the amount of tiles available, theres only 5 tiles in this build.

Changes Over Build 4029

Bugs and Known Issues in 4051

Frequently Asked Questions (F.A.Q.)

Q: Why is my Longhorn CD not bootable?
A: Because the original release was missing its boot record. You will need to obtain a fixed ISO or find a patch to make the CD bootable.

Q: Does the memory leak still exist in Explorer?
Unfortunatly, it does, but there are two solutions to repair the leak or stop it completely. Read the rest of the guide for more information.

Performance Tweaks
Here's where the fun begins. This build has a lot to be tweaked to speed it up so here we go!

Uninstalling un-needed components:

Now navigate to Add/Remove Programs in the Control Panel
Go to Add/Remove Windows Components

Uninstall the following:

Disabling Unnecessary Services:

Go to Start --> Run and type Services.msc
Now set the following services to DISABLED

Performance Options:

Now go to Computer properties --> Advanced Tab, under Performance options click the Settings button.

Uncheck the following:
(all of these are optional, but the ones marked VERY IMPORTANT are best to disable)

Now open Computer and go to Tools --> Folder Options and click View Tab and uncheck the following:

The Infamous Explorer Memory Leak
Everyone remember the explorer.exe memory leak that was present in 4015 and 4029? Well suprise! Its still here! Good news is it can be capped off for good with a few simple steps.

  1. Start by disabling the sidebar (right click sidebar --> properties uncheck Enable Sidebar)
  2. Go into Computer, go to tools --> Folder Options, View Tab and check "Launch folder windows in a seperate process"
  3. Right click Computer and go to properties, Advanced tab, under performance hit settings and uncheck "Show preview and filters in folder"
  4. Now reboot and there will be no more memory leak. The sidebar has pretty much been turned into a waste of space in this build, and filters are sort of broken in places, so theres no real need to have them turned on.

Explorer Lag when opening My Computer

This bug either happens or it doesn't. It depends on your hardware configuration. Particularly if you have a scanner or not. If you have a scanner you will most likely experience a very large lag when opening the My Computer window. The only way to fix this is to go into services.msc and disable the Windows Image Aquisition Service, yes this will stop your scanner from working so do not use this method unless you don't use your scanner or if you value speedy explorer browsing.

Repair Longhorns Networking

In terms of Networking, build 4051 is sort of.. well.. messed up. You may not be able to browse some computers' network shares or even the entire network itself. To fix this, follow the instructions below.

  1. Make sure that your workgroup is set the same as all of your other machines. You can change this by clicking the Windows flag (Start), right-clicking on My Computer, and selecting Properties. Click the Computer Name tab, and then click the Change button. Change the workgroup name and press OK.
  2. Restart your computer.

After performing the above steps you should be able to browse through network shares and other network related items without any problems.

Networking Fix For Longhorn – Static IP Kills the Internet

Longhorn build 4051 sports a rewritten TCP/IP stack which in a lot of ways is nice, but it has more than its share of bugs. One of the most critical bugs is that changing to a Static IP in network settings will kill the network route going to the gateway, which in turn kills the internet connection. At first I had no idea how to fix this and then i began to dig and found the problem.

The problem is that the gateway route (as i mentioned above) is gone after switching to a static IP. It can be fixed by using a DOS command, see below.

To fix the Internet route in Longhorn 4051 open the command prompt (Start --> run, cmd.exe and press enter). Type the following:
route change mask x.x.x.x metric 1 if X
x.x.x.x is the IP address of your gateway and X is the metric ID of your network card. See below on finding the metric ID.

Now your Internet will work. Good and dandy right? WRONG! After a reboot it will be messed up again so here's what you have to do. Put the command i mentioned above in a bat file and save it to C:. Then go into gpedit.msc and navigate to Computer Configuration --> Windows Settings --> Scripts. Double click startup. Click add and point it to where you saved the batch file. Now on every reboot it will fix the internet before login.

Cannot Complete the Network Setup Wizard
(Thanks to Samael on xBetas for figuring this out)

To set up a network you must have permission to configure Internet Connection Sharing, Internet Connection Firewall, and network bridging.

Control panel --> Click on user accounts --> Click on "start the network identification wizard”

MSN Messenger Auto Sign-in Bug
(Thanks to Samael on xBetas for figuring this out)

Problem: MSN Messenger does not auto sign-in on boot even if you tell it to.


  1. Find MSNMSGR.EXE and right click on the icon
  2. Select properties
  3. Select Compatibility
  4. Select windows 2000
  5. Check Mark the Allow non-administrators to use
  6. Click ok all the way back out
  7. Relogon and make sure to check automatically sign in.
  8. Voila its working right!

Screenshot Section

Here's a few screenshots of different features in Longhorn, more will be added if i find anything worth posting.

Computer Window - Computer (Formerly My Computer) window open showing the slate design on explorer windows.
Contacts Window - Shows the look of the Contacts window with filters off (filters cause memory leak too).

Longhorn Help Center - The new help center which sports a new and somewhat promising look.
Hardware And Devices - Notice the carousel view that was in 4029 is not in here. I wonder why they removed it.
You'll Like this one - The only screen of my main machine of all of these, just had to throw this in to give you guys something to envy :P.


Copyright 2003 Chris123NT and Nighthawk.