Can I install IE10 Preview for Windows 7 and keep the previous IE8 version for development testing?
I don't believe you will be able to run IE8 and IE10 side-by-side on the same machine. Instead, I would encourage you to use the browser-emulation options found within the F12 Developer Tools. From there you can instruct IE10 to behave as though it were IE8.
If emulation isn't desirable, and you're not interested in downloading a virtual machine image, you could also consider exploring the BrowserStack service. It will allow you to spin up IE8 on multiple versions of Windows, and view both remote and local files.
Also consider IETester - http://my-debugbar.com/wiki/IETester/HomePage
You can run tabs side by side in different browser versions. Works well for my web dev testing.
You may consider VMware thinApp (virtualize Application) or Microsoft RemoteApp (Run application from remote server).
In my environment, I have amix of thinApp and RemoteApp (some application virtualized (ThinApp) and then accessed using RemoteApp).
MS started an extra Homepage for IE testing. Lots of options under http://loc.modern.ie/
I think this is a more reliable option for developers
IE 1-8 Standalones
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