I recently ended up with these files in the root of one of my drives. On digging, came to know that these are temporary fiels created during the installation of Visual C++ Redistributable 2008. These are erroneously created in root of one of the drives instead of temp directory.
Check Microsoft article here.
These can be safely deleted.
This is fixed in later versions, if you have somehow ended up installing an old version and you see these files in one of the root directories, you can safely delete them. I somehow ended up installing this older version(I think I installed it while trying to fix an issue with my printer) and these temp files were created in my F drive which I use for storage(not OS) while my OS in in C drive.