Modem-3 (HUAWEI MT880):
Step-1:
Invoke Internet Explorer. Type the IP address 192.168.1.1 in the address bar. You will get the screen shown bellow.

Step-2:
Type username and password as “admin” and “admin”. Click OK. You will get the home page of HUAWEI. Select WAN Settings. You will get the screen shown bellow:

Step-3:
In password box clear the old password and type the new password. Click Submit button.
(Note: You should not change the username.)
Step-4:
Select Tools in the Main Menu. Select System Setting.

Step-5:
Click Save&Restart button.
Step-6:
Switch off and switch on the modem. Connect to Internet and enjoy.