I've just updated to WP from 4.4 to 4.5.1, which made most of my network crash. I've updated all plugins and themes now and everything seems to be working, except a specific subdomain:
When i try to login i get Error 500. The website works fine, its only login that gives issues.
I haven't found any other sites that doesn't work so far. I've granted access so you can take a look.