When you'll upgrade a project solution for the first time, get this message error:
And also return this:
C:\Users\Admin123\projects\Firmware\LHF-100\SI-LHF-100.cproj : error : Value cannot be null. Parameter name: url
Buuuut, if you try again, it can be migrated as well.
Isn't a annoying bug, is just something to improve. And this error only at build 7.0.783.