No header error trying to install "multisite plugin manager"

Hello I am starting my multisite network fresh from scratch with only buddypress network activated so far. Im following the multisite setup article on your blog step by step. So be it, Halted at the first step with this error and failure to install. What does this mean? I found the same question asked about this error a few places trying to find an answer myself but there was never a reply to any of them so it seems the no header error lays unresolved. Ill try to give admin support access through my wpmud dashboard if you felt like takin a boo. Kind of stuck and awaiting your reply :slight_smile:
Thank you.