can't connect two PCs thru a switch ?

I want to share folders between my two computers A and B. Would also like to share internet thru ICS. Both the computers have windows 7.

This is the setup - One direct lan connection from router to A, then another lan on A is connected to a switch. B is also connected to a switch.

On A, I have allowed other network users to connect thru this computers connection (for the lan card which is connected to the router).

The other lan connected to the switch remains unidentified, in fact it gets APIPA with IP as 169.254.82.6.

What am I doing wrong here pls ?

The configurations sound unnecessarily complicated. If the router is also a modem then it simply needs pc's A and B each to be connected directly to the router using DHCP with no need of ICS. They would then be on the same LAN and folder sharing can be set up provided A and B are on the same workgroup. If the router is not the modem and the internet connection is via one of the pc's then ICS may be achieved using either the router and DHCP or without a router at all, just connecting A and B with a crossover cable and setting compatiible IP addressing on the two pc's.

Yes, you are right. It can be done both ways as cited by you.

But, I am deliberately trying to network through switch.... let's say - am testing and learning !

Ok. A switch is by definition a layer 2 device which means it can communicate to connected devices via their layer 2 mac adresses. (This fact is complicated by the introduction of "layer 3" switches but we'll ignore that - assuming you are talking of standard layer 2 deices). This means that all devices connected are on the same LAN - layer 2 devices cannot connect between devices which are not on the same network or subnetwork. Provided you meet that requirement then a router connected to the switch with two or more pc's attached to it should be able to communicate with the internet and with each other.

When I connect the router to the switch, and my magicjack with two computers to the switch, all can access internet.

When I connect router to PC A, and A connects to switch, B also connects to switch, I cannot access internet on B, is that what you mean to say ?

Not directly - you cannot connect B to the router through another PC. Given the configuration you just described I guess you could then set up ICS between A and B but it would seem a pointless and inefficient way of doing something which can be achieved much more easily and efficiently by direct means via the router.

I know it is pointless. But I need to do this on somebody's else home. In fact, connect more than one computer. I want to do ICS sharing along with files and printer ? This is what I am looking for.

Thank you patcooke, your replies are very informative !