I downloaded the April CTP Windows Phone 7 tools, eager to test out an idea I had for some geolocation action. Installed Bing Maps Silverlight Control and fired up VS2010 and…cue sad trombone…
A first chance exception of type 'System.IO.FileLoadException' occurred in mscorlib.dll
Brandon Wilson from the WP7 team posted the details but it turns out there is a bug the latest bits where by the WinPhone OS will only load assemblies signed with a Windows Phone Certificate – i.e. are part of the Windows Phone 7 SDK. As Bing Maps is part of the Silverlight SDK it won’t load. Game over.
There is a work around, which involves hacking the Bing Maps assemblies and removing the certificate from them. Brandon has a PowerShell script for doing this. It creates a copy of the Silverlight assemblies and strips the certs from them so the WP7 will load them. You then have to reference the hacked assemblies instead of the real ones.
Unfortunately this didn’t work for me. I’m not sure why. Probably there is some assembly along the chain that still has a cert but I don’t really have the time to work it out. Alas my goelocation genius idea will have to wait another day (or until the next CTP refresh).
Tim Heuer also has some info.