I just recvd my new MiFi 4510L successfully connected to my laptop with 4G service. I went into the web Admin to change the Admin password & network password. After changing it I tried to re-connect to my laptop and it said the network password was invalid (I didn't enter the wrong password as I had a screen print of the new pasword as entered via the web admin). I tried the default password also and that didn't work. Tried both multiple time. Rebooted the laptop & powered on/off the MiFi several times, took out the battery & SIM card and re-installed and nothing worked. It was late and I called Verizon and tech said the device wasn't charged fully. He said it needed 4 hours although it had been charging for 3 hrs and the battery symbol had 4 bars that were not moving (light was blinkin yellow when powered off). He said after 4 hrs of charging take off the cover and hold down the reset button for 10-15 seconds & this will restore it to the default network password and admin password. I let it charge 1 more hour and used the reset button. Display lit up with all he symbols when I did this but the default password didn't work when trying to connect from my laptop. Tried this several more times, did the battery removal/SIM card removal, power on/off and nothing worked. Any advice on what is wrong of did I just get a lemon device?
I found that the default password is different for different versions of the Mifi4510L. Hopefully, the information from this site may be more helpful in deciphering your default password.
Default Router/Admin Password is always "admin"...unless something has changed with the most recent models. Use the router password to sign into the MiFi admin page (http://mifi.admin)
Default wireless password will be unique for every device. This is what you use to connect to the device. You can find the default password on the white lable on the back of the device. If your label is missing/removed then you can decifer your default wireless password from the IMEI number underneath your battery. Let us know if you need the steps to convert the IMEI number into the wireless password.
My guess is that the OP has a cached password on his computer which needs to be removed. On WinXP you can use the following steps to delete the cached wireless password and start fresh.
Delete the saved/cached password in WinXP:
Let us not get confused. There are 2 different passwords involved. The web paget used to make changes to the settings. That password after a hard reset (Press the reset button until all icons turn on on the LCD) is admin. The other password is to connect to the wifi and that is on the sticker on the back of the unit, only unless you have not done a hard reset. After a reset if you can not connect using the password printed on the sticker, try using the 14 digit IMEI number printed on a lable under the battery. Omit the -X part of the number. Even though the docs state the newer devices revert to the password on the back, that is not always true, some revert to the IMEI number, as the password.