Is the router/modem in bridge mode? Are you connected Lan to Lan or Wan to Wan?

Yes, the modem/router is in bridge mode. They are connected with a LAN cable so I suppose LAN to LAN.

So you put in information for virtual server without any errors. What step in the process do you receive an error? After checkingt http://www.portchecktool.com/, is it soemthing like this:

Problem! I could not see your service on wan IP[B] on port ([B]5000).
Reason: Connection timed out.[/B][/B]

I get no errors when creating virtual servers but when I use a port checking service (I usually use canyouseeme.org) it says the port is not open. Also, my NAS is no longer accessible from outside of my network and that's the whole reason I wanted it opened to begin with.

Are there any other settings I must activate on the TP-Link that might have been reset during the firmware update?

Have you tried different ip addresses and ports? Your ISP could have blocked particular ports.

Which modem gateway do you have? I know one of my CG3000d had hidden menus.

Other than using DMZ, there are really no other settings to try. There is the convenience of DDNS, but will not work if ports are blocked.

When you upgraded firmware, did reset to factory default and manually enter in settings or did you saved configuration?

I've tried a different ip and a different port and my ISP is not blocking ports.

What do you mean by gateway?

The TP-Link automatically reset to default when I updated.

Gateway = modem/router. The more I thought about it, I do not think it would matter. If two routers were cascaded, then you would need to setup routing tables and port forwarding. But since your gateway is bridged and providing a pubic wan, that will not be an issue for establishing remote access.

http://portforward.com/help/doublerouterportforwarding.htm - this is to what I was referring