Seems like, Microsoft may of finally pulled the plug on Windows Update servers for Windows Vista :(
Not only that, but Microsoft has also pulled the Windows Vista Service Pack downloads off their website too.
Anyways (not trying to advertise), but I have the Windows Vista Service Pack 1 32-bit along with 64-bit, also SP2 32-bit and 64-bit available for anyone to download.
To top it all off, I have all of the Vista updates up to April 2017 (32-bit and 64-bit), downloaded with wsusoffline.