Sagemcom 2704n Port Forward Issues

[#1]

Hello,

Having read multiple posts prior to posting this, I see this is a general issue for owners of the Sagemcom 2704n Router, but I haven't found a solution as yet.  It is my hopes someone here can help me.

I have successfully forwarded ports for my CCTV system (34567) FTP Server (21-23), Remote Desktop (3389) etc. without any issues, however I now need to open ports 465/587 for use with GMAIL/CCTV alerts and also need to forward a few custom ports for custom apps/hardware.  I have forwarded these ports in EXACTLY the same manner as I have the working systems above, yet when checking online (www.canyouseeme.org) it shows those ports as closed.  I have tried disabling Windows Firewall completely (Windows 10) and can confirm I have no other software that would interfere with this.  DMZ also doesn't work when running port forward tests e.g. ports 25467, 8000-8099 (tested ranges).

So, my questions are, is there a limit to the number of "working" port forwards that this router will allow simultaneously, are there lockdowns in place for specific ports and how do I resolve these issues?

Kind Regards

Mal.

[#2]

IIRC your Plusnet Broadband Firewall may be blocking those ports. Even on Low setting I believe those ports are blocked. Log in and check. If not, I'd keep the setting on Low. If you change it, remember to drop your PPP session and reconnect so the changes are activated.

[#3]

There have been posts on here before about Port forwarding issues on this router. I think that someone managed to get it working by turning off IPv6 on the Expert User / Advanced Settings / Lan / IPv6 auto config page.

http://192.168.1.254/expert_user.html

Login details are the usual ones you use to log onto the router.