You've just installed Windows Phone 7.1 Developer Tools RC but you were unable to debug it.Right?


This is because some files are missing from your PC that Emulator needs.
Lets run Standalone Windows Phone Emulator and see which file it is!






See? MFPlat.DLL file is missing from your PC! This problem here isnt about running VS2010 as Administrator or not! I saw guys talking about this so often but they are focusing on the wrong direction :) The real problem here is: our emulator needs this MFPlat.DLL file.
So where to find it?
Dont worry i've Google'd around a bit for you and found the required files that will help you run WP7.1 Emulator properly.


First of all, download the archive file i'm giving you.



Now extract these files.
There are 3 folders: "C_Windows_System32" , "C_Windows_System32_en-US" and "C_Windows_SysWOW64"

Copy the 3 files inside these directories into the same location as folder name given within archive file.


Furthermore:
1) Copy mfplat.dll inside "C_Windows_System32" folder into C:\Windows\System32 directory.
2) Copy mfplat.dll inside "C_Windows_SysWOW64" folder into C:\Windows\SysWOW64 directory. (if you're using 32-bit Win OS, ignore this step)
3) Copy mfplat.dll.mui inside "C_Windows_System32_en-US" folder into C:\Windows\System32\en-US


After this step you're ready for WP7.1 Development!




Hope it helps!