Thanks for your reply.
Yes, there is no picture, although I had insert the image link between
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previously.
Here is the web link:
http://tinypic.com/view.php?pic=11ul061&s=9#.Vl4Oo3arRhE
OK. As your suggestion, I check and know that the printer is DHCP. Then, it is no use to reserve a static IP for it.
The problem is that the printer IP (DHCP) was given 192.168.0.100. I don't know what reason it was changed to 192.168.0.101. And my PC (original was 192.168.0.101) was changed to 192.168.0.100. This resulted the printer driver cannot see the printer. I don't see any method to fix it except change printer IP address manually now.
The relevant information on the problem is clear to understand now?
Thanks,