How do you fix a DLNA Protocol (401) Error?

A year ago, my stepfather got a new router from Vodafone; since then, I have had problems with my PSNetwork. My playstation connects perfectly fine to the internet, however the same error message (401) always pops up shortly afterward claiming it is unable to connect to the media servers needed to fully access my game's potential. I've searched on the PSNetwork website and it wasn't helpful at all, only gave me fixes for two error codes that had nothing to do with my problem.