Is there any way I can install silverlight plugin for Firefox without admin privileges? For Flash there's an .xpi extension so that I can install it on Firefox Portable.
The installation of Silverlight itself requires admin privileges, so even if there was an .xpi installer it wouldn't really help.
It sounds like you can't; sorry. (Though you should probably search around some more before taking my word for it.)
I was able to extract and "install" Silverlight 3 as a plugin for FirefoxPortable v3.6.10 and SRWare Iron (Chrome variant) v6.0.475 using the techniques listed in this conversation at PortableApps.com, and the files from the Silverlight 3 SDK.
Netflix streaming and the few other tested Silverlight applications worked fine. Netflix gave me errors (perhaps DRM issues) on my first attempt with the latest Silverlight.
To summarize the steps:
agcore.DLL coreclr.DLL microsoft.visualbasic.DLL mscorlib.DLL mscorrc.DLL npctrl.DLL NPCTRLUI.DLL silverlight.configuration.EXE silverlight.configurationui.DLL sllauncher.EXE slr.dll.managed_manifest system.core.DLL system.DLL system.net.DLL system.runtime.serialization.DLL system.servicemodel.DLL system.servicemodel.web.DLL system.windows.browser.DLL System.Windows.DLL system.xml.DLL
protected by studiohack♦ May 3 '11 at 9:51
Thank you for your interest in this question.
Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site.
Would you like to answer one of these unanswered questions instead?