Having same problem. This only happens when connecting via 4G/LTE - when connecting via 3G port forwarding works just fine. Please mail tech support, the more people complaining, the quicker somebody will look into the matter.

I've already sent you a PM how you set you modem to 3G only. I have a Huawei E398 modem but changing the option in the computer Dashboard doesn't change it in the modem itself.

Hi, just plug the usb modem straight into your pc. Start the dashboard software that comes with the modem ( the utility that that auto installs - Mobile Partner or what it is called) one open and sim card was detected, go to Tools then Options. In the Options Tab, go to Network and then Network type. On the drop down select WCDMA only, click ok and close Mobile Partner app. The setting is now saved on the modems config. Plug the usb back into the tp-link router and the router will now connect only via 3g.

You can reverse this again by plugging the usb back into the pc and go to option ....... And then select LTE only or Auto. Hope this helps.

Thanks for the detailed description! I have done as you've said but "WCDMA only" was already selected in Mobile Partner software. Did it with another dashboard as well and there was also "WCDMA only" selected. So I guess your workaround doesn't work for every modem. I hope TP-Link will soon release a new firmware.

I can only confirm that i have the same issue with E398 and TP-MR3420 V2. If it is like some of you say, 3G works but not 4G it is probably a firmware/software bug, because in E398 3G works like a serial connection and 4G is NDIS. The internal firewall in TP-MR3420 is probably listen on serial instead of NDIS. I have tried this with the modem connected to my Dovado 4GR in bridged mode and then connect to the WAN port and it works perfect, but when i connected E398 direct into 3420,s USB it won´t work, i can surf normally but no open ports.

Sad but true, TP-Link has to write a new firmware to fix this :(

/Mats

TPLINK have been very slow in implementing full support for 4G/LTE modems.

Huawei 4G modems have a different response to mode and band commands.

You will also find, if you are in an LTE location that gives speeds greater than 25Mbps, that the V2 will (most likely) hard limit at 25Mbps.

The Tiny will support speeds up to 88Mbps (lan connection).

It is pretty bad form, that TPLINK have released a 3/4G modem ... that does 4G so poorly!!

this problem occurred when LTE only connected, seems it cannot work totally within this kind network. maybe TP-LINK left out something?

Hi,

To get the port forwarding working on LTE mode, mail support and ask for beta version mr3420v2_en_3_13_31 . Port forwarding on LTE and 3G works perfect with this version

hi guys I've written to the support but no one has answered me, so anyone has the beta firmware to test if it's possible to use the forwarding ports with a 3g connection ?
Everythink works fine with WIFI but from remote and with dongle inserted the ports are not forwarded, and I have no access to any resource.

I hope someone has the beta firmware or a solution.

regards Matteo Masina

Do you have full remote access by the IP address any restrictions from ISP?