Hello to you Goober42!
Thanks for trying out both of those sites! I'm sorry they're not working out for you. I know how important it is to have access to the admin site so I will be more than happy to provide you with as much detail as I have available.
First and foremost the computer you're using must be connected to the internet connection the 890L provides. If you're connected to anything else (Wi-fi, dsl, cable, etc) it won't take you to the appropriate page.
The sites you used (http://192.168.1.1 and http://vz.hotspot are both accurate. The 890L suggests Internet Explorer 7.0 , Mozilla Firefox 3.0 , Opera 10.0 , Safari 4.0 , or Chrome 5.0 .
If you're still having issues I would master reset the device by following these steps: http://support.verizonwireless.com/clc/devices/knowledge_base.html?id=50011
Let me know how this goes!
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