Time Capsule+Comcast not playing nice.

Welcome to the discussions!

"Call Comcast Tech support. Hour later, multiple resets, and nada."

My experience with cable modems in general is that they need to be powered off (and the battery pulled if it has one) for at least 30 minutes and often longer to completely reset.

I'm sure that your ISP will say that this doesn't apply to their modems or system, but power it off for an hour or longer.

Can you check a setting on the TC using AirPort Utility, Manual Setup?

Click the internet icon at the top of the setup window and then look at the bottom of the pane for the "Connection Sharing" setting. It should be set for "Share a public IP address".

Give it one more try. If still no luck, I would suspect a defective Time Capsule.

As for the Linksys, sounds like it was not in a default mode which would allow connection sharing among several computers. It was probably set to "bridge mode" which would do exactly what your experienced.

writerchad,
I've been here searching the internet and found you...the exact same problems I am having. I have done all you've done except trying another router.

My Time Machine backs up but the internet only works when I'm plugged directly in to my Mac. I also have Comcast. I've always had it but recently switched to comcast phone, too, which required a new modem and that is where my problems began! I am unable to get wireless thru my Time Capsule for my laptop and to make matters worse, even cannot plug my laptop directly in for successful web browsing.

Did you ever find an answer or have any success?!?

writerchad/mch123
I'm in same boat... just upgraded Comcast cable modem... previous was old(but worked fine)..setup was modem to D-link router out to Imac and TC. W/new modem d-link doesn't work, do I figured I'd just use the TC and wired and wireless router..... no go! Modem to Imac everything is great, throw TC in the middle and I get nothing.... wired or wireless...... Anybody get any answers???

Two things that worked for me... 1.) I stopped using comcast DNS addresses, go to OpenDNS.com and use their DNS addresses. and 2.) Power off your modem for at least 20 mins. ( I also powered off the TC and the computers), hook everything up, power up modem, when its done power up TC and computers... in that order. Have your TC set up to create wireless network and to "share a public IP address". Thats what worked for me... Good Luck.

What worked for me - reset your TC and create a new internet connection - power all of the devices off - TC, Comcast modem and your mac computer. Turn on TC first and make sure you have the green light. Turn on your Comcast modem - after it gets all of its lights, turn on the mac computer.

Just wondering if the power down/up 'stuck' for you?

1. I have Comcast and previously a Belkin wireless modem. We decided to streamline our backup and wireless so bought the Time Capsule. Set it up using the Aiport Utility (Connection sharing is set to Share a Public IP address). Internet works fine when plugged directly into Modem. Time Capsule works fine for 24 hours then orange light starts flashing and Comcast Modem (RCA) starts resetting (Four lights flash then each individual light fires up). Leave it long enough (over night) and it finally everything comes back online without intervention but then goes out again several hours later and starts again. I call Comcast, they say something is causing the modem to reset, they come out to the house (twice) and check the lines all the way back to the box, every thing is working fine when plugged directly to the Comcast Modem. Problem starts when Time Capsule is plugged in - although it works fine for an initial period then disconnects.

2. Contact Apple Care (twice). They say the issue relates to Comcast providing a private IP address not a public one when connected to the Time Machine. We go through a number of settings and Apple Care decides to send out a new Time Machine. According to Apple Care it appears to me that when the TC us unplugged Comcast sends a public IP address but when the TC is plugged in and reporting errors its is because there is a private IP address.

3. New Time Machine received. Set it up using same process as before. Works great for 24 hours then out again! Seems to be the same problem when the TC is plugged into the modem it is getting a private IP address (a 192.... number). The problem continues to be sporadic. Works for several hours then down for 8-10 hours (a side note I am nursing a newborn so I have an opportunity to check the TC status several times during the night!)

Of course I can power down every time this issue happens but on that basis I would be doing it a couple of times a day. Comcast and Apple Care have been responsive but unable to resolve the problem.

Any further ideas? I was interested to hear if you are still experiencing these problems.

I will have to call Apple Care again.

I just thought I would chime in on this thread. I just moved from San Francisco to Atlanta and here I have the RCA modem mentioned above. Last night, suddenly, the modem apparently went on a blink and I couldn't access the Internet. I tried restarting it several times and plugging it back in the right order (cable modem first, then Time Capsule).

Since I have both a TC and an AirPort Express I quickly found out it wasn't a base station problem, since they both wouldn't work. So, I changed the "Share A Public IP Address" setting and turned it off the RCA cable modem for more than 30 minutes and it worked.

I hope this doesn't repeat itself as in the above case. If so, I will have to replace this RCA modem. I had a Motorola cable modem in San Francisco and only had to reboot the modem twice in three years of use. 😟