Koumak

Just FYI. FW has been reloaded througth the DSL port from ISP to valid and funcional one. I reload after that the not branded fw by using "zycli" settings to do not check the fw version ABPM6C0. Now i stopped the analyze of situation, i do not have enougth time to analyze Zyxel change from version ABPM0C0 which i currently…

I underestund you, i has different problem with another fw and also with IPTV which not working with absolutely standard configuration, which works on another devices. Zyxel started to be untrustworthy company for me. What about to try Mikrotik HW for your solution, some are very cheap and working well. :-)

Maybe you can try the solution from another comment: https://community.zyxel.com/en/discussion/5912/vmg8823-increase-number-of-static-dhcp-entries-is-it-possibile

Hi, manual for VMG says that: Subnet maskEnter the subnet mask, eg 255.255.255.0 (default). The Zyxel device calculates the subnet mask based on the IP address entered, so don't change it unless you're absolutely sure what you're doing. Maybe it helped, but to be correct i never used different than defaul subnet mask. 

Hallo dear community, my issue still persist and i still did not find any solution. Anybody help please.

Another question is if it is possible to upgrade firmware without knowing the "admin" user password? I did not find any way. Does anybody knows, how to do it?

Hi Tony, thanks for the answer again, but your question do not make sense if i wrote, that both VDSL modems i set the same, it means the firewall has been set for the MEDIM at both. But i underestund your question, just describing the similarity of the configuration. I have in another problem, i found "somwhere" the FW…

Update of information from my analyze. I runs my VMG3625-T50B on FW version V5.50(ABPM0)C0 and IPTV correctly works. I tried on another VMG3625-T50B the FW version ABPM5, ABPM6 and today ABPM71, which i found at the official Zyxel pages. These versions has problems with actual streaming of O2 CZ IPTV programs. If i move…

Hi Tony, many thanks for the link to the firmware. Unfortunately the firmware version V5.50(ABPM.6)b5_V0_20210906 can not be replaced by the one, i found at your link, it means version V5.50(ABPM.6)C0. The modem reject this firmware. Do you have any other suggestions what to do? BTW Happy New Year to you too :-)