What's the easiest way to install multiple versions of IE and Firefox on the same (virtual) Windows machine?

I could obviously have multiple VMs, but that would be highly inconvenient. Is there some easy way to have multiple versions of browsers installed simultaneously? It's mostly about IE and Firefox; other browsers are not popular enough to make testing with their old versions a terribly high priority.

Solution 1:

I have had luck with this: http://spoon.net/browsers/

Launching a virtual browser takes a couple seconds to load, but less of a pain than multiple VM's.

Solution 2:

Internet Explorer
Our team struggled with this some time ago, and we found that neither IETester nor Multiple IE provide a solution which you can rely on if you want to get the same results as native IE users.

The best solution is the native "virtual" one. Microsoft itself provides Virtual PC disk images for individual versions of IE (disregard the expiration date on their page, they should release new images once the current ones expire). Note that you can download Virtual PC from the Microsoft site for free (the page above contains a link), but for some reason they have a broken link there at the moment.

The only disadvantage of the above is that Microsoft does not provide an image for Windows XP SP2 with IE6 (the SP2 version of IE6 uses an older Javascript DLL, so it behaves slightly differently than the newer SP3 version).


Mozilla Firefox
You can test individual versions by using Portable Firefox from the PortableApps suite. The linked page offers the newest version, but it also contains links to older (legacy) versions at the bottom.

Please note that by default this won't allow you to run multiple versions of Firefox simultaneously. It's possible, but it requires some simple hacking:

1. download a portable version of FF from the site above, "install" it into a folder
2. go to {your FF vX.Y folder}\Other\Source, locate and copy a file called FirefoxPortable.ini
3. go back to {your FF vX.Y folder} and paste the file there
4. open the file in a text editor and change the following:
   • add -no-remote into AdditionalParameters
   • set AllowMultipleInstances to true

If you setup each version of Portable Firefox as shown above, you will be able to run individual versions simultaneously.

Please note: this is for development purposes only. If you use FF as your primary browser, include it in the "mix" only at your own risk. We're using it only for testing purposes ourselves, and even though we did not encounter any problems so far, I would not want you to lose/corrupt your primary FF profile.