The reason that we need to enable adminpldt account is to fully manage our fibr router such as Port Forwarding, Wifi settings and more.
Here are the steps to re-enable adminpldt account:
1. Browse http://192.168.1.1/fh
2. On Administrator field, enter: fiberhomesuperadmin
3. Then on Password field, enter: sfuhgu
4. Then click Login button
5. Click Debug Switch Menu
6. Switch On (Enable radiobutton) Web Admin Switch
7. Click Apply button
8. Click Logout link
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9. On Administrator field, enter: adminpldt
10. Then on Password field, enter: 6GFJdY4aAuUKJjdtSn7dC2x
11. Then click Login button.
12. After enabling Web Admin Switch, just browse http://192.168.1.1/fh
The steps will not persists on power off.
Proof that it works...