Hide "Logged on", "# programs running" on WinXP Fast User Switching

Use software such as Stardock Logon Studio to customize the logon screen. You don't need to change it entirely – just delete the two links.

To do it manually, use a Win32 resource editor such as ResEdit or XN Resource Editor to edit resource UIFILE:1000:1033 (type UIFILE, ID 1000, lang 1033) of file %SystemRoot%\System32\logonui.exe.

The part you'll have to edit/remove is lines 939 to 940:

            <button id=atom(status0) class="status" layoutpos=none/>
            <button id=atom(status1) class="status" layoutpos=none/>

The element with id=atom(status0) displays %d unread mail messages, and id=atom(status1) is for %d programs running.

Disallow SYSTEM from reading the HKCU\SessionInformation registry key.

1. Open regedit
2. Expand My Computer → HKEY_CURRENT_USER
3. Right-click on the SessionInformation key, choose Permissions...
4. In the name list, select the SYSTEM entry
5. Under Permissions for SYSTEM, check the Deny box for Read.
6. Click OK.

You will have to do this separately for each user's registry. Also, I am not sure if these changes will persist after logoff :(