The fact the Apple works throws a wrench into the one idea I have. But I'll write it anyway, just in case.
You noted the firewall in the PC but what about the firewall in the router. Did you turn that off for a test run?
As to the program installed that blocks, only you know what's installed besides windows own.
Hi
I am having difficulty with my pc. I have expereinced constant problems with my HP printer. The printer is conected wireless to the router. Now that I have installed the new WP MyCloud to my router. The software does not find the harddrive in my network.
I also have a MacBook in my system that does not have these problems. I can print and I successfully installed the hardware.
When I ping the IP address of the printer on my PC, it would answer that it cannot reach it. However, when I ping my router, it found find it.
Reading on the internet brought me to the suggested solution that there might be program installed that blocks my computer from accessing / communicating with these network hardware.
I have obviously tried turning off the windows firewall. However, that did not give me any solution.
Does anyone have a good way to approach this?

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