A network is what allows multiple computers to communicate to one another. It is also required for your computers to to talk to a router through a network to gain access to the Internet.

In the case of Retailer, a network connection is what allows multiple computers to use Retailer and access your data, which is kept on the main/server computer. Other PCs will not be able to use Retailer if they cannot communicate with your main/server computer over a network. When you have issues with your network, it may prevent your slave/client computers from starting Retailer or cause Retailer to respond slowly or even freeze at times.

If your POS computers are unable to open Retailer ('No Retailer Data Found' error), check to see if they can access the internet - eg. try to google something. If the internet is also not working, it is a sure sign that there is a problem with your network.

Below are a number of steps that you can take to resolve basic network issues.

Problems with the network are caused by factors outside the Retailer software and are not covered by Tower Systems Support.

Make sure your routers and/or switches are turned on

Routers (occasionally referred to modems) and switches (sometimes called hubs) control your network. If they are not turned on, the network will cease to work.
When turned on, they will have lights on the front.

Below is what routers and switches look like.
A simple way to tell them apart is routers normally have antennas as they provide wireless connectivity as well.

Make sure no cables have been unplugged

Network/Ethernet cables have clips or latches that keep them in place when plugged into the router, switch and/or computer.

Check the router/switch to make sure all cables are plugged in securely.
Do the same for the computer, and make sure the cables are plugged in securely there as well.

Power-cycle your routers and/or switches

Router and switches are specialised forms of computers and as such, are also subject to "freezing" during operation.

To resolve this, simply unplug the power cable and leave it off for about a minute.
This fully drains the power from the device and allows it to perform a complete restart when you plug the power back in.

Restart your computer

The Windows operating system has processes and services that control network connections.
Restarting the computer will restart these processes/services, which may resolve network connections.

Contact a Computer/Network Technician

If you still have issues with your network, your best option is to then employ the services of a local computer/network technician.

They will have proper tools and resources to resolve issues with your network connections.