Follow the guideline? The VLAN part.
https://www.dlink.com.sg/wp-content/uploads..._Setup_Card.pdf

Maybe you are going to the wrong page, try click on the "Port Forwarding" on the left side of "Save" button.

And yes, I know that they are similar feature, except Virtual Server allow you to change different port for local and remote.
But worth a try.

Also here is the guideline for setting up multiple port forward for single local IP address/machine, don't forgot to remove the config saved on "Virtual Server".
http://support.dlink.com.sg/Downloads/DIR-...ulti-ports..pdf

If still unable to access via WAN, try disable the "Enable SPI IPv4" on Firewall settings, some SPI on router is too strict and causing issues to some features.


If still unable, well, try upgrade the firmware, it is v3.10 for the latest version, the upgrade page should allow you to "Check for New Firmware" and upgrade to latest version.

https://www.dlink.com.my/DIR-842/#firmware
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Just a warning, the DMZ is the last, not recommend method, if after disable SPI and upgrade firmware don't solve your port forward issues, then change your router, or having a CCTV that having better method to bypass the Firewall(like connect to the cloud, but that is another privacy issues la).

This post has been edited by BenYeeHua: Jul 23 2019, 07:07 AM

Just follow this until step 6, don't change the interface to IPTV at step 7, and you will having your 4 port for internet use.

And just FYI.

http://support.dlink.com.sg/Downloads/DIR-...-and-TM(MY).pdf