Today I tried to access the admin panel for a basic Wordpress site. It has no plugins, and uses the default theme. I haven't modified any files. Any admin url returns an HTTP 406 "Not Acceptable". What's going on?
I found this which might solve your problem:
This code goes in a file called
EDIT: @Rarst is right. It is just to see if the problem is here. You'd better not to leave this in