Today I got great news: my invite for the Windows Phone 7 Mango Beta arrived. Installing it however requires that you first install Beta 2 of the Windows Phone 7.1 SDK. When trying to install that though I encountered the error of "Visual Studio setup cannot run in compatibility mode. For more ...." etc etc.
*update*
It seems the error above stems from the fact that the Beta 1 of Expression blend for Windows Phone 7.1 was installed. The Beta 2 of the Windows Phone 7.1 SDK checks for the presence of PSDK 7.1 Beta 1 but apparently not Expression blend. Removing Expression Blend for Windows Phone. Removing Blend and re-running setup fixed the installation problems.
It seems the error above stems from the fact that the Beta 1 of Expression blend for Windows Phone 7.1 was installed. The Beta 2 of the Windows Phone 7.1 SDK checks for the presence of PSDK 7.1 Beta 1 but apparently not Expression blend. Removing Expression Blend for Windows Phone. Removing Blend and re-running setup fixed the installation problems.
I'll keep the instructions below in case they are needed as some intermediate step but likely you wont need them
A quick fix for this problem seems to be to extract the contents of the WebInstaller (vm_web2.exe) manually and then run the 'setup.exe' contained therein under administrator privileges. (just running vm_web2.exe as administrator seems to be insufficient) Below are some screenshots of the steps involved.
Nothing overly complicated but I hope it saves some others a few minutes of searching.
-Leon
Pic 2: Having installed Winrar right clicking on the vm_web2.exe executable displays the 'extract to' option we need for this
Pic 3: once extracted we select the 'Run as administrator' option for Setup.exe and we're off.
