Although developers consistently tell me that IE6 should no longer be supported, I continue to find reasons why our clients still need to support IE6. I discuss these reasons more in two previous blog posts here and here.

As I mentioned earlier, I have found that testing websites for IE6 compatibility is a bit of a pain because IE6 is not designed to run on a machine that is running IE8. In the past, I’ve typically been able to get an additional, older computer that was running IE6 for testing purposes. However, I’m finding that it’s more difficult for me to find an IE6 machine than it used to be.

Fortunately, I have found 2 free tools that Microsoft provides to make testing websites on IE6 easier: Microsoft Expression SuperPreview and the Internet Explorer Application Compatibility VPC Image. In this post, I’ll write about the free IE6 VPC Image. I covered SuperPreview in an earlier post.

What is Internet Explorer Application Compatibility VPC Image?

Microsoft actually has a number of OS/Browser combination VPC images available for free. Here is Microsoft’s description of the images:

"In order to help web designers and web developers test their websites in older versions of Internet Explorer, we’ve provided the following VHD with Windows set up with the specified version of Internet Explorer. The images are patched with the latest security updates and are otherwise clean installs of the operating system with very few modifications."

For those not familiar with VPC, the concept is that you have an entire additional virtual machine available on your computer. When you open up the VPC, the experience should be essentially the same as using a different physical computer. In this case, you can easily experience what a user would experience when using IE6 on Windows XP.

Using Internet Explorer Application VPC Image

In order to use this free tool, Microsoft says that you need a minimum of 3.0 Gig hard drive space free to expand the VHD file. You also need to have Virtual PC installed on your computer. I already had this installed when I started. If you do not already have Virtual PC, you can get it for free from Microsoft here.

When you open Virtual PC, you click "Create virtual Machine" at the top.

The wizard that comes up is pretty easy to follow. The key is that on the last step, you will need to select "Use an existing virtual hard disk" and select the .vhd file that you downloaded from Microsoft.

After you complete that step, you will see the virtual machine in the Virtual PC tool. You simply double click to start the machine. There are ways that you can improve the integration between the Virtual PC and your computer; however, that is beyond the scope of what I am covering here.

At this point, you have a Virtual PC that is running IE6 on Windows XP. As we saw in the SuperPreview tool, my company’s website has some problems rendering properly in IE6. The main image is pushed below content that is on the right hand side of the page. This is a problem that I have seen on many sites during compatibility testing.

The website is completely dynamic and Virtual PC can be set up to have all of the same rights and permissions as the computer that you are logged into. I tried using this through a VPN, and it worked well. I did some cursory comparisons between this Virtual PC and a laptop that was actually running IE6 on Windows XP, and the two systems seemed to demonstrate the exact same behavior.

Drawbacks to Internet Explorer Application VPC Image

The only major drawbacks that I’ve found to using the free VPC Image from Microsoft are that the image can take up a lot of space and it has slower performance than my primary operating system. The space issue can be easily handled with external hard drives if necessary. The performance issues are quite minor on my environment, so it is not truly a problem for me. It may be an issue for some machines.

The VPC image does not have the debugging tools or side-by-side/overlay comparisons that are available in SuperPreview. So, you may want to combine both free tools from Microsoft in order to complete your IE6 compatibility testing. The VPC image can be used for end-user testing and testing of the dynamic features. SuperPreview can be used for finer debugging and design comparison work.

Other Tools for Testing Browser Compatibility?

I’d like to know if you have found any additional ways of testing your website in IE6 or any other browser. The two solutions that I’ve found from Microsoft should help, but I still haven’t found a really good way to test Safari on Mac short of having a physical Mac computer with Safari. This is often not practical. I look forward to hearing about your experiences.