Disable your plugins via FTP (rename the folder) and see if you can get in.
Ok i will organize my points
1- ever since i upgraded to wp4
my admin username which i used to login was drashrafsabry now all of the sudden it changed to admin
2- i can log in
but the area which i used to click to find network setup and to administer network plugins and themes dissapeared
3- both my Arabic drashrafsabry.com and English drashrafsabry.com/en are working front and back but there is no place now to add new site or administer network plugin or themes
I’m facing a similar issue. After the upgrade, i can see the dashboard list items, but on clicking on any of them, its a blank page or i get data not received error.
Read http://halfelf.org/2013/recovering-your-cape/
Your user ID should never have been changed (WP really can’t do that unless you have a weird plugin) so it’s possible you were hacked or someone with access changed permissions.
Well
4 days ago i was hacked , my front was defaced by a group called ISLAMIC HACKERS.
I logged to the database and changed my username from admin to my original , i found another user with empty username i deleted it , as soon as i did so , my network setup was back again !
