Given these are yours to command, only you know your requirements and could create a script or app to report in on a schedule of your choosing. Be aware you are asking a very well worn question so not much has changed in over a decade. That is, you detect a machine going down by its silence or it not checking it. We know that PING can work when the machine is up or down so that's no test at all except of the network connectivity.
Time to write a script that does what you need.
Bob
I am looking if there is a specialized app for this or whether TeamViewer is the best option. I have to work with 3 separate corporate networks from my command station where I have 3 separate workstations. These 3 workstations are each using their own network of the three 3 total networks. The workstations consist of 1 PC running Windows XP and one of them uses Windows 7. Each one of the 3 networks is connected to 3 remote workstations in a different city. There is a program that alerts me whether the network is up or down in each of the 3 networks connected to the remote workstations. But in order to know if the computer is running and alive, I ping the computer name or the IP address. Sometimes though pinging doesn't work if an administrator changed a firewall setting and the IP addresses sometimes change as well.
If I had TeamViewer running on all remote workstations I know that if I can log into TeamViewer on the remote workstation in question then obviously the computer is running and alive.
But I would like to get an alert that lets me know if a computer isn't running instead of my actively having to check using something like TeamViewer. Is there some application that would do that for me?

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