Thanks for your response.
The print is local( for myself use only). If click the print icon, most time will pop up a window says:
This document failed to print.
Document name:.......
Printer name: "HP HSC 500"
Time sent: .....
Click here to open the print queue, and then for assistance, click troubleshooter on the help menu.
If I go to print queue, I tried cancel or restart or other thing, there is nothing I can do but restart the computer to make it work.
Can you tell me WHY?