i just tried to hook up printer to pc with USB and downloaded latest version of windows driver from canon website which is 2111 .Yes. Much clearer now.
The short version being that working laptops and a PC are being used on two different all wireless networks. Network #1 for Internet and Network #2 for printing via a router shared USB printer. The networks are completely separate.
All working laptops can succesfully switch between the wireless networks, using Network #2 for dedicated printing.
The PC is unable to print via Network #2 and is the only computer unable to print on Network #2.
Very much narrows the problem down to the PC provided that the preceding sentences are correct.
First try a direct USB wired connection between PC and the Canon 6030. Verify that a direct USB connection between PC and printer does indeed work.
If not, then troubleshoot accordingly. You may need to reinstall the Canon drivers on PC. Do so by directly downloading the drivers via Canon's website. Manually install and reconfigure.
Once direct printing (PC < ----- USB cable ---- > Canon 6030 printer) is proven to be working then focus on the wireless configurations relevant to the PC and the DLink 2750U/Canon 6030.
Disconnect the wired USB connection and set PC back to Network #2.
Ensure that only the PC's wireless network adapter is enabled. (Wired adapter disabled.)
Simply first test to determine if the PC is now able to print wirelessly.
Failing to print:
1) Look in the PC's Reliability History for any error codes, warnings, or informational events that occurred when printing was attempted.
2) Port 631 uses tcp and udp protocols. Because all other computers can print verify that the PC is using the correct protocol to print.
Using PC's Command Prompt run "netstat". Compare the results to the results of the working (able to print) computers.
"security option is on the 1st mode (use anonymous account) and other two are using windows OR use specific account..... and thats all.
but on my problematic pc , i see a huge box with a lot of options and on top is the Ip adress same as this one but configurable (my laptop is not so) and also a lot of other options"
On the PC take a close look at those configurable options. What each option is and what the option does.
Google, research (User Guides/Manuals) for more information.
Post what you find and learn.
when it opens up, it ask for ways to connect and obviously i chose USB connection. but it won't install anything and says no printer is conected. kinda strange while other laptops are fine.
BUT, in device manager its ok and recognized! even i could print stuff through USB on problematic PC.