The network does not work on computers?

Question

Squid

In general, the network organization is like this, there is a tp-link (192,168,1,1) with the Internet, a cable goes from it to linux with squid (192,168,0,2), from a squid from the second network card there is a cable to a server such a switch wide in which computers with Windows are plugged in, before everything was buggy, now two computers seem to be unable to access the Internet there is a yellow exclamation mark and do not see the network drive located on this linux with a squid. Addresses are set manually, what's the problem? On the squid there are some rules that will not allow anyone to connect to the network. Later I will write what, now I do not know. Squid is a gateway, the mask is 255.255.255.0 and addresses from the pool 192.168.0.3-254 do not see network 4 and 74 at the ends they are not visible in this figure

Answer 1

and the ports on the switch, into which these two losses are plugged, are alive? peretykali in other ports?
the switch, if anything, is:

such a wide server switch into which computers with Windows are plugged

Answer 2

Exclamation point!
1. Remove the drivers from the PC network card
2. Reboot the PC. install from the update, or the manufacturer's website.
3. Insert another network card and see how the PC works

Answer 3

If I understand correctly, according to your screenshot, the switch has an address on the network (0.254).
Try to ping it from problem computers.
If there is no ping, the problem is on the way from the computer to the switch.
Either a cable, or, as a colleague correctly noted above, with a network card (hardware / driver) on these computers.