How to Set Up IE6 on Windows Vista

I'm running Window Vista Home Premium edition which comes with IE7.  I tend to use Firefox for my main web surfing.  For work I needed to see if SpongeFish runs ok in IE6.  If you're on Windows XP or earlier, you can use  Multiple IE to run multiple IE versions on your machine, but not so for Vista right now.  The alternative I went for was downloading Virtual PC 2007 (free) and running Microsoft's IE6 application compatibility virual hard drive (also free, but the virtual hard drive is time bombed to be good for only some number of months). 

In brief:

1. Download Virtual PC 2007 from Microsoft.  Vista Home Premium is not officially supported for running Virtual PC 2007, but so what, I got it working.
2. Download the IE6 application compatibility virtual hard drive for Virtual PC.  This is a massive file.  Plan on doing plenty of other stuff while you wait.
3. Set up Virtual PC running the IE6 virtual hard drive.  My experience was slightly different than the one I linked to, namely in substeps 4 and 6 below. 
   
1. Start Virtual PC and click "New" to start adding your IE6 virtual hard drive.
2. Select "Create a virtual machine" on the first screen of the wizard and click Next.
   
3. For Name and Location, name it whatever you want (I chose the very creative "IE6") and put it where you want.  Click Next.
4. For Operating System, select Windows XP.  Click Next.
5. On the Memory screen, you can adjust the allocated RAM.  Default is 128 MB, I went with 256 MB.  Click Next.
   
6. On the Virtual Hard Disk Options screen, you want to choose to use an existing virtual hard disk.  This is what you downloaded above: the IE6 application compatibility virtual hard drive.  Or IE6ACVHD, if you prefer.  Click Next.
7. Virtual Hard Disk Location: click browse and select the IE6 virtual hard disk you downloaded.  Click Next.
8. You should be at the confirmation screen with your new virtual machine name, memory, and virtual hard disk that you'll use.  Click Finish. 
   
9. Your Virtual PC console will now have your new rockin' IE6 virtual PC instance.  Select it, click Start, and the virtual PC will launch.
4. Add the Microsoft Loopback connection and configure Internet Connection Sharing on your Vista machine network connections
   
5. On your Vista machine, go into Network Connections and get the Properties of your network connection to the internet.  Click on Sharing tab.  For Internet Connection Sharing, check "Allow other network users to connect through this computer's Internet connection" and in the Home networking connection drop down select the Microsoft Loopback connection you created in step 4.  Click the Settings button on this tab and turn on the services you want.  (I'm doing browser compatibility testing, so I turned on HTTPS and HTTP.)  Click OK.
   
6. Hooray!

Note that once you have this set up, you can get Multiple IE on this VPC to test additional versions of IE.  I didn't go this far as all I needed was IE6.  

Other bits:  

• This guy says that you may have problems with Virtual PC 2007 recognizing your wireless network adapter, but I didn't have any issue with this.
• I did have problems with my home wifi connection after changing my network connection configuration to get Virtual PC working.  When I'm not running Virtual PC at work, I disable the loopback adapter and turn off the internet connection sharing for my main internet connection and everything is fine.