Originally Posted by Mr Pink57
Wirelessly posted (your electric?: MOT-A-1C/01.01 UP.Browser/18.104.22.168.c.1.104 (GUI) MMP/2.0 UP.Link/22.214.171.124)
It does require a certain amount of charge before use. However that does seen like a long time since it just displayed the message and you immedially put it on a charger.
My wife has a 7520, I asked her and she confirmed that it does need a certain amount of batter life, but if she plugs it in right away, she can use it within a couple of minutes. She said that she has never waited ten minutes after plugging it in.
I a carry spare battery, I'm on mine too much to worry about a drained battery.