I have two computers connected to a network switch and every once in a while one of the computers will lose its internet connection. It's almost always the same computer every time. However, if I play around with the control panel, I can switch it, so that now the other computer is not connected. Restarting either of the computers does not help either. In Windows, the worlds-greatest-trouble-shooter tells me that a network cable is unplugged and that I should try plugging it in...Disabling and re-enabling my NIC does not fix this problem, neither does swapping cables around. When rebooting, the BIOS complains about how the Ethernet Cable is not plugged in.

If it's in any way important, My set up at the office is like so:

Modem -> Routher -> Network Switch 1 -> Network Switch 2.

I have tried turning off the energy saving option for my NIC, and I tried manually setting the link-speed to 100Mbps Full Duplex without any luck.

Also, I have a Realtek PCIe GBE Family controller on both computers

Does anyone have any idea why this is happening every 5-10 days?

EDIT: I have also tried using a completely different Network Switch and the problem still persists as before.