Looking for [link|http://support.microsoft.com/search/default.aspx?query=error+1706&x=0&y=0&catalog=LCID%3D1033&spid=&qryWt=&mode=r&cus=False|Error 1706] in MS's KnowledgeBase turns up several hits. The [link|http://support.microsoft.com/kb/299803/en-us|2nd one] looks like a pretty good fit. Try the "MEDIAPACKAGEPATH" thingy - somehow. Maybe that'll help.
I'm sorry this is rather obscure. All I know about this is what I've been able to Google. Good luck!
Cheers,
Scott.