if it is under hardware warranty, and you cannot get into it at all. It is possible the unit has failed, and there's not much that can be done about it. go to the Cisco site, hover over support --> open or view cases, create a case there, then call in with an existing case. phone numbers here
You could do a packet capture (wireshark is a good tool) and if the device has a static IP address, there should be an ARP broadcast packet coming out. Then set a static IP on your pc on the same subnet. You should then be able to get to the GUI...
If it is provisioned and locked down, that can prevent factory reset, and in that case you should return it to the place of purchase for one that works. or ask them for the password.
If you used a credit card and the vendor will not give you one that works, you can reverse the charge with them.
Network Address Translation (NAT) Settings for Lines on PAP2T and SPA3102 Phone Adapters
The objective of this document is to configure Network Address Translation (NAT) settings for the lines of communication on the PAP2T ...
Speed Dial Settings on SPA100 Series
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Firmware Upgrade on SPA112 and SPA122
To upgrade the firmware a specific file must be downloaded from the Internet and uploaded to the device. Upgrading your devices can be very useful. Firmware upgrades can fix software bu...