Off the top of my head, here are possible issues...
1 - bad USB cable. Try using a different cable. (also, try a different USB port on your computer.)
2 - windows drivers. Try updating to the latest drivers. You can grab the latest from samsun...
Could you please post xposed log? What language are you using?
Inviato dal mio GT-I9505 utilizzando Tapatalk
stupid question but what is the app i want to freeze if i dont want to keep getting the update reminders? im having a hell of a time searching for it.
AT&T Software update