after i long into my account the screen is blank

Check /var/log/ajenti.log and search here with any error messages you find.

Hi, same problem but /var/log/ajenti.log: File o directory not found

I've edit: /usr/lib/python2.7/dist-packages/socketio/handler.py

then:

("Access-Control-Max-Age", 3600),

changing it to

("Access-Control-Max-Age", "3600"),

I've fixed!