I have a Windows 10 PC and was trying to sets up a LAN connection today. Wireless works fine, but I was getting some ping spikes so I wanted to rule out my wireless connection as a cause. Anyways, the LAN connection works when it's plugged into the Cisco Linksys E4200 Router (which is plugged into an Embarq 660 Series modem, quite old). It also works when it's plugged directly into this 660 Series modem.
However, it reads "unidentified network" if I try to plug into the combination modem/router on my other internet line. This is the unit: http://internethelp.centurylink.com/internethelp/modem-pk5001z.html It has 4 Ethernet ports on the back, one of which is utilized by another PC with no issues whatsoever. I have also had no problem connecting to this router wirelessly.
Any suggestions would be fantastic, it's been driving me a little bit mad.

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