I accidentally disabled http/s administration over LAN on Zyxel T-50 thinking that I was disabling them for WAN. Modem works fine, Internet connection is fine. I just lost access to the admin interface,
SSH and telnet appear to be disabled on this device hence I could not apply the workarounds I found on the web.
Is there an easy way of enabling http/s and/or ssh/telnet on this device, or is a reset required?
Hi
Oh-oh! I'm here to help. Of course, a factory reset will most likely be the surest solution. You say you disabled the LAN. Is it still possible to logon to the modem (192.168.1.1) through Wifi? If not, that I guess the only option is the reset: Factory reset modem.
Will you keep us informed? 
This is the setting change you can make to the Management to still be able to get into your modem, but to get back into the mode use
The only thing you can switch off .. and you should .. is the Ping (ICMP) response.
BTW Happy and for all Healthy New Year
Resetting the modem resolved the issue. My customizations such as static DHCP entries, APN name and password changes got lost but not a big deal.
Modem established the WAN connection right away after the reset and the LAN clients were able to resume their connections. I reapplied my setting changes and took a configuration backup this time.
Thank you both Sander and Pieter_B. Wishing you a happy new year!
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