I read very often things like “Should work, cause its downward compatible”. But I’m too long in the business to trust sentences like this – so basically If I write a Silverlight 3 App for a customer I want to test it with the SL 3 Runtime, if I play around with the new SL 4 Features, I obviously need SL 4 Runtime. Are you like me ? Don’t you like VMs for these small requirements ?
It took me a while to figure it out. My Solution is based on Firefox Portable and these are the steps to do:
1. First uninstall your Silverlight 3 Runtime to be able to install Sl 4
2. Then Install SL 4 Runtime. You can download it from Microsofts getStarted Page
3. Copy the Files C:\Program Files\Microsoft Silverlight\4.xxxxx to a temporary Folder
4. Uninstall Silverlight 4 and reinstall Silverlight 3. If you don’t have the Runtime at hand, you can download it Here. (I could not find the actual Download-Page or a Runtime-Archive. You can help me out here ?
5. Copy the temporary saved files to your Firefox Portable Folder under \Data\plugins
Done that, the IE (and the Rest of the System) uses the installed SL 3 Runtime, while your Firefox Portable uses the SL 4 you copied to the Plug-in Folder.
The only downside is, that the Silverlight-Info within the Browser will show Version 3, cause that’s the officially installed one on the System.
Anyway, I did a few tests, and everything seems to work fine. Let me know about your experience with this.
