Public Ip asking for login credentials

[urgenthelpneed]

Hi,

I am using an old Dell laptop on which i have installed Windows server 2008 r2 and recently brought a static ip from my ISP. My ISP had setup the static ip on the modem which is a d-link and my modem is connected to the Linksys router wrtg54 which gives is DHCP enabled and my ip for the router is 192.168.192.1 and right now my server laptop i am using through wifi.

I had installed IIS on it and successfully configured FTP on it and i can access ftp internally but not externally through public ip.

I have given 192.168.192.103 static ip on my server and forwarded port from modem to router and even from firewall inbound setting.

I had also tried DMZ setting from my modem as well router it still dont work.

Completely closed firewall on my server

Checked with the ISP if port are closed or open they confirmed ports are opened.

My main concern is that

"I cant access my ftp outside my network" it ask for login credentials which i havent setup on my modem or on my router.

I am stuck on this from last few days i would really appreciate if someone can help me with this.

[icecream-guy]

the credentials being prompted are probably from your modem?

you'll probably need to setup some sort of port forwarding on the modem to allow ftp to the server.
i see that you did that,

is there a route on the modem to get to the server?

i see that it looks like you may be getting to the server, do you have local server credentials to user for login to the ftp server?

[deanwebb]

i see that it looks like you may be getting to the server, do you have local server credentials to user for login to the ftp server?

This was also my thought.

[Rllavona13]

Do you have 2 routers doing NAT ? or just 1? Maybe the double NAT is doing that.