If you are on Cox Communication’s Premier plan and your modem is disconnecting when you try to upload anything all you’ll likely have the D-Link DCM-202.

Yesterday, Cox increased the speeds for Premier plan customers. Upload speeds were increased to 4 or 5 Mbps, downloads increased to about 25Mbps. Unfortunately Cox messed up and didn’t apparently test that their upgrade would work all modems on their approved list. The D-Link DCM-202 has massive problems with uploads on Cox’ new setup – it disconnects if you are trying to upload anything. Once you stop the upload attempt, the modem will reconnect. Downloads should be fine but even those might be affected.

Cox didn’t feel it’s necessary to at least acknowledge this problem on their web site so many customers were, like me, totally caught off-guard about it and have to figure this out on their own. The DCM-202 is one of the most widely used modems so there are probably lots and lots of customers who are undoubtedly freaking out right now. Lovely service, Cox.

Cox’ new infrastructure works best with DOCSIS 3.0 modems. The D-Link DCM-202 and almost all other currently available modems however are only DOCSIS 2.0 compliant. Apparently, D-Link is the only modem manufacturer that currently has these problems on Cox’ new deal. Cox and D-Link supposedly are working together to figure out what the problem is.

Since you’ll likelyneed your internet to actually work right now and not when Cox and D-Link get around to working things out you will need to get a different cable modem. Luckily, you can buy any common cable modem (for example, the Linksys CM-100 you’ll find at Target and Staples works just fine) – just don’t buy another D-Link DCM 202. It just won’t work.

Ideally you’ll purchase Motorola’s SB6120 modem though – it’s the only DOCSIS 3.0 compliant modem Cox can work with (disregard the Cisco modem they have on their list – according to a rep I spoke to, that one is not supported right now either). The Motorola SB 6120 also one of the few DOCSIS 3.0 modems currently available on the market. But you might need to order that one online – I was unable to get one at any of the Fry’s Electronic stores or three other electronic places I went to. It’s sold out everywhere apparently, at least at the time of this writing.

So summary: if you’re on Cox Premier and have the D-Link DCM-202 go out right now and buy a different cable modem. I hope this helps you and saves you hours on the phone with tech support and running around town trying to find the SB6120.