Hi, I have an HP laptop with a builtin wireless card I have also installed a USB TP links wireless card so that I can connect to 2 different wireless networks. However, as soon as I connect the second first one gets disconnected and vice versa. Anything I can do to make it work.
You should be able to make it work but it is tricky to actually do anything useful with it.
The 2 networks need to have different IP subnets. But that is the easy part. Your largest issue is that your computer does not know which network to use for what purpose. You are going to have to tell it that for example you want netflix to use network 1 and youtube to use network 2. This is all done with the route command. It is rather tedious to do.
The only things that is not real hard is say you had a internal security network with no internet. Then you would just remove the default gateway from that network and leave the other nic standard. Since the lan subnets are different it still knows how to get to the devices directly on the subnet.