Is your Internet service connected all the time? Also where are you trying to install from, installation media, or your online account?
I assume this is Windows 7 SP1 and totally up to date with IE11 etc. (even if you never use it) ?
Maybe you are using a wireless connection. Have you tried it using a LAN ?
You say you ran MCPR but was it a fresh installation of it (it updates constantly so always has to be freshly downloaded) from HERE and you must reboot immediately afterwards.
You may try using LAN instead of Wireless as suggested by @Ex_Brit and reinstall Mcafee Antivirus Plus. Both MVT and Mcafee Antivirus plus would require steady high speed internet connectivity. If you think internet connection is good, it would be in your best interest if you could contact support for speedy resolution.