i started a installation when my wifi & my LAN both are enabled
it threw me a Error saying the installer cannot proceed with current internet connection setting. (it was taking my direct connection to internet as first preference to download)
i disabled my wifi so only MY LAN connection was enabled.
I clicked Retry in the error message, there was no operation to install after that.

it is sometimes seen by unplugging your network cable before installation , after error plugging it in & clciking retry.