Multiple Incoming Connections via VPN?

I've had an old PC that I've been experimenting with and have been turning into a NAS for my data so I can access it whenever necessary. I currently have the built-in Windows "Incoming Connections" VPN set up, and I've got it working good. But in the future I plan to have others be able to use it as well, but I'm not able to get more than 1 incoming connection to it at once. I've researched this a bit and from what I can gather this feature does in fact only allow 1 connection at once. Does anyone know of a way to allow more connections, or a third-party application that can create a VPN connection that accepts multiple connections? I've tried Hamachi and this does work, but I don't want to have people need to install another application for this (also, it's only free for 5 people). Answers appreciated!

I'm facing the same issue. ryley, did you come up with a solution?

Have you taken a look at OpenVPN ?

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