1. Download Virtual PC 2004 or Virtual PC 2007 onto your computer (Windows XP or Windows Vista)
2. Unzip and double-click on Microsoft Virtual PC 2004 MSDN.msi to install the Virtual Machine using the Installation Wizard
3. Download Windows XP SP3 with IE6 VHD file from Internet Explorer Application Compatibility VPC Image
4. Double-click on IE6-XPSP3.exe to install IE6 XP SP3 image
5. Read and agree the License Agreement
6. Read the disclaimer and take note of the Administrator and IETester passwords
7. Choose C:\ or anywhere you like as your destination folder and click 'Install'. The Installation Wizard window will disappear once it has finished installing
8. Start 'Microsoft Virtual PC' on your computer (Default location: "C:\Program Files\Microsoft Virtual PC\Virtual PC.exe")
9. From Virtual PC Console, click 'New...'
10. Click 'Next >' on New Virtual Machine Wizard Screen 1
11. Select 'Create a virtual machine' option and click 'Next >'
12. Enter the name for your New Virtual Machine, eg: IE6 XP SP 3, and click 'Next >'
13. Choose 'Window XP' as the Operating System and click 'Next >'
14. Choose 'Using the recommended RAM' and click 'Next >'
15. Choose 'An existing virtual hard disk' and click 'Next >'
16. Locate the virtual hard disk on your computer. This is the one you installed previously using IE6-XPSP3.exe. Browse into that folder (for example C:\), select the vhd file (XP SP3 with IE6 2008-Dec.vhd) and click 'Open'. And click 'Next >'
17. Click 'Finish' to close the wizard and create a virtual machine with the settings you specified

Now you can start IE6 XP SP 3 anytime on your computer by selecting it from the Virtual PC Console and clicking on 'Start'.