As I see in (
http://www.kinook.com/Forum/showthread.php?t=4500) VB analyzes sln files only to determine version of msbuild which has to be used. It seems it is a root cause of my problem as I don't have sln files for lots of my projects. Only vcxproj-files.
I hope VB team will fix it and in next versions the VB will analyze vcxproj-files as well.