first question would be what version of either blender are you using?

newer versions are available in 32 bit and 64 bit and if you have a 64 bit system and download a 32 bit software it will not work right sometimes because it downloads into the x64 files and not the x84 files where it needs to register

if by chance you got one of the OS or ubuntu versions they will not register at all

check which version you have and need and make sure that they are compatible

also do all windows updates and retry the download