Port range error

SSenturk

Hello, 
I am using zyxell DX3200-B0.
Model Name = DX3200-B0
Firmware Version = DX3200-B0-V7.0-20220119
Network Setting -> NAT->
New add Role Service Name = WAN Interface
Start Port = 25
End Port = 25
Translation Start Port =25
Translation End Port =25
Server IP Address =192.168.5.200
Protocol = TCP
AND = OK
Error Message = Port Range Error
And DMZ = 192.168.5.200

25ports not work.
What could have gone wrong?
Thanks

YeK

hi SSenturk,

The fw version of your device is customized, please contact with your ISP to see if it's an limitation or not. 

SSenturk

Thank you for your suggestion.
The problem was fixed by the ISP.
Thank you.

SSenturk

Thank you for your suggestion.
The problem was fixed by the ISP.
Thank you.

smb_corp_user

Yes, it is common for most ISPs to block port 25 to fight spam traffic.

SSenturk

I think my question was misunderstood.

Port 25 is open by ISP.

Cannot register port forwarding 01 to 80 in currently available software.

Unable to register NAT.

DMZ is not working.

I need urgent help.

SSenturk

I found a solution.

I threw this modem in the trash.

I bought a new modem of another brand.

After that, I swore not to buy anything Zyxel at my workplace.

It ruined my 1 week email traffic

Thanks everyone.