After repairing my Windows XP Prof SP3 installation, I had an issue with my sound. There was no volume icon in the taskbar & I couldn't install Microsoft UAA and I found out none of HD audio/modem devices where recognized even after installation of the correct drivers from the motherboard manufacturer because of the wrong UAA.

This fix from http://www.boredsysadmin.com/2008/03/windows-xp-sp3-and-microsoft-hd-audio.html solved my issue.

If updating the UAA doesn't fix your issue, you may want to try this fix http://forums.lenovo.com/t5/T61-and-prior-T-series-ThinkPad/No-audio-device/m-p/15874#M5711. It was instructed below.

1. Chek if PnP SW Enumerator is installed on your machine (Device Manager -> System devices) - should be listed there!
2. If it is not there then we will probably solve it!
3. Locate machine.inf on your OS, copy it your Desktop and modify it (find ExcludeFromSelect=* and remove the line or simply exclude it from processing by adding a ; at the beginning).
4. Still with machine.inf open, search for SWENUM and check the location of SWENUM, mine reads like this SWENUM.CoInstallers.CopyFiles = 11 ; %windir%\System32
5. Find swenum.sys file on your XP installation CD (mine was in DRIVER.CAB) and copy it to the proper location (I am not sure if it is necessary but worked for me)
6. Go to Control Panel -> Add/Remove Hardware and follow the wizard towards manual selection of device to be added
7. Select Add System device
8. Select Have disk
9. Navigate where the saved machine.inf located (as per Step 3, it was sasved in your Desktop).
10. From the list select standard deviecs (in the left list) and Plug and Play Software Enumerator in the right list
11. Finish the installation

If it still does not work reinstall the audio adapters' drivers. It should work now.

I was trying to install Windows SBS 2008 (64-bit) for trial, but I keeps receiving this error from Virtual Box everytime I tried to Start the system.

I enabled the Hardware VT from the BIOS (under Security menu) and restarted the computer - still the same error.

I disabled the Execute Bit from the BIOS - still the same error.

I untick Enable VT-x/AMD-V in VirtualBox Settings->System->Acceleration - it gave a different error.

I even downloaded the SecurAble to double-check if my virtualization & DEP are enabled, same with the 64-bit capacity - yes, I have virtualization & DEP enabled in my BIOS & I have 64-bit.

I also tried editing the XML file %systemdrive%\Users\%username%\.VirtualBox\Machines\<OS name>\<osname>.xml and type "false" for enabled of <HardwareVirtEx enabled="true" exclusive="false"/>

Shutting down the computer and leaving it off for 5 minutes fix the issue. I now have Windows SBS 2008 (64-bit) as the guest OS of my Vista (64-bit) parent OS.

First step to try:

- boot computer from Windows CD and choose repair (R)
- from command prompt run: chkdsk /r
- when checkdisk finishes, remove Windows CD and boot WindowsXP normally.

Second step to try:

- Follow procedures from Microsoft on how to recover from a corrupted registry that prevents Windows from starting  http://support.microsoft.com/default.aspx?scid=kb;en-us;Q307545

Thirs Step to Try:

- made sure ACPI, Plug & Play, USB all enabled in BIOS
- moved mouse from the ps/2 port to the first USB port
- booted using Safe Mode
- waited until it hung at Mup.sys
- removed the mouse cable from the USB port
- (3 seconds or so pass, the screen went black and safe mode appeared)
- restart the system
- boot normally into XP

After repairing Windows XP or after replacing a motherboard, you might receive this error before logging in "This copy of windows must be activated with microsoft before you can log on."

• Download this patch which works for Windows XP Home and Prof.
• Reboot to Safe Mode.
• Open the downloaded file and double-click AntiWPA3.cmd
• Click Yes when it prompt.
• That should be it.
• Restart the computer and you should be able to login now.