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I've been trying to forward port 21 with no success. I have a CN router that has many options, but I have basically no idea what is what.

I have already forwarded the 21 port, but when I check it online, it says it is closed. Any ideas?

I have a DHCP server on (whatever that might be) on the with my computer being on .11. I have tried it with the DMZ host as my computer, but that also didn't work.

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migrated from Mar 26 '11 at 16:02

This question came from our site for system and network administrators.

Your isp might be blocking port 21 so it might be worth it to also try changing to a non-standard port. – Brandon Mar 26 '11 at 15:55
from the isp : only blocks port 25 (inbound and outbound SMTP with permission) to reduce spam (junk e-mail). – Bartlomiej Lewandowski Mar 26 '11 at 16:05
up vote 1 down vote accepted

see if you have a server running on port 21
C:\>netstat -aon | find ":22"

C:\>telnet 21

see if that gives any text.. If so good..

make sure your windows firewall or other firewall isn't blocking it..

do ipconfig or right click your network connection and click and get the IP suppose it's

Go to another computer on your network and do telnet 21 see if you get the same text. If so good.

Now do the port forwarding in your router. Then do the online port scan on port 21.

That should work so port 21 comes out as open.

But as for getting FTP running, there are issues like passive FTP and active FTP. I'm not that familiar with that.

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was the win firewall problem, fixed, thanks:) – Bartlomiej Lewandowski Mar 26 '11 at 20:50
you could now generally block it in the windows firewall but allowing some ip or range of ips.. would be a bit more secure. should still come out as open when connecting from the computer you want to. you could allow the ip of the online port scanner so that gets through too! – barlop Mar 27 '11 at 23:47

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