Q: Internet connection lost after sleep - Ethernet

Negative, captain. I deleted all 5 files and rebooted, but that didn't solve the problem.

I'm not sure who the captain is, but I was wondering if you restarted the modem and/or router too. I had to shut everything down.

And, I'm beginning to think you 10.6 people do have a special problem.

Tonight after five successful days with a new iMac 27 i5, when I brought the i5 out of sleep and went online, there was nothing but a blank page. Diagnostics said there wasn't an internet connection. However, my iPhone and PS3 were able to connect. All of the modems lights were green. I turned the modem on and off anyway but to no avail. I then unplugged the ethernet port and then I got that circular colored "hour glass" instead of the curser. i tried Control Eject and the shut down screen appeared but would not respond. Finally, i had to power off the bad way by pressing the power key. i turned the wireless router/dsl modem off and back on, powered up the computer and then all was well. Any clue?

Hi there from germany, I have the same problems with my new iMac 27" i7. Could it be that no one has a solution for this problem? I have got use all suggestions but nothing works. When I see how many clicks are in this topic it seems to be a general problem. Is there no solution from Apple Service?

Same problem with my iMac 27" i7 and airport extreme.

After waking up from sleep, no internet connection, while all other devices on the network (macbook, windows laptop, iphones, PS3) are fine. The iMac has network access - I can ping other devices, just no internet access.

What seems to be causing this is the "wake for network access" setting in energy saver. When turned on, no internet after wake up. When off, internet connection's fine after waking up I can consistently reproduce the problem. When the setting is off, of course, one cannot share printers, music libraries, etc., without first waking up the computer manually, which is annoying.

I'm pretty sure "wake for network access" was not causing this before. I've been using the iPhone remote app to control iTunes (although I haven't used the app lately) and the iMac would wake up and play online radio stations without a hitch. I suspect Apple introduced this bug recently.

I have the same problem. I found this but haven't tried it yet. Can anyone confirm if this works?

"Happy to say the long time to connect after Mac wake up is solved. I had to go to the Network Prefs, select PPoE, and de-select the box for "connect automatically when needed". That prevented the computer from trying to connect via PPoE settings in the Network Prefs instead of via the Airport Extreme. Since I set the AP utility to connect via PPoE, it does, and there is no longer a conflict.?"

What seems to be causing this is the "wake for network access" setting in energy saver. When turned on, no internet after wake up. When off, internet connection's fine after waking up I can consistently reproduce the problem. When the setting is off, of course, one cannot share printers, music libraries, etc., without first waking up the computer manually, which is annoying.

I have the same loss of internet when my MacMini 10.6.2 wakes from sleep. It only seems to occur if I put the computer to sleep, not when the computer goes to sleep by itself. If I sleep the computer myself it enters a deeper sleep (hard drive spins down, etc.)

De-selecting the "wake for network access" setting in energy saver makes no difference for me.

I should add that we have two MacBook Pros on our wireless network with the same problem. If the computers enter a deep sleep (if you close the lid), when you wake them up the internet doesn't work. Sometimes it takes several minutes for the internet to start working again.

Using an Airport Base Station Extreme and DSL.

As many other owners of the new 27", i've had same problems with slow internet, websites hanging. I tried EVERYTHING along with Apple Care (=no help at all!) and web forums.
Reformatted the machine, deleted profiles, changed router channels, changed encryption method, changed between b,g and n.
All my other devices worked flawlessly, including, pc's, laptop and iphones.
Problem was solved when installing Win7 !!! via Bootcamp.
So I concluded there definitely must be a conflict between my router and the airport firmware/driver.
I changed my router from Netgear 614v5 to another (not apple) and all problems are solved!
I've tried to address this problem at Apple, but they couldn't care less. The answer was more or less: If you don't have an Apple router, we can't help you.

Have just downloaded and installed 10.6.3. Release notes indicate that there have been some changes made addressing problems like this. Just waiting to see whether it has fixed my specific problem...

Lasted just over two hours before the same old problem arose. Connection still active but a check on the network diagnostics from System Preferences showed the Internet and Server lights yellow while everything else was green.

After fiddling with some of the network settings previously discussed in this thread I rebooted, but same thing occurred after about 7 hours, then again after a further 12. I'm not even putting the machine to sleep (other than the display).

Continues to frustrate and irritate.

I upgraded to 10.6.3. today in the hope my airport issues would go away (I was optimistic based on fixes to stability/reliability stated in 10.6.3 notes) .... but alas it still does the same thing. I think it has improved slightly, but it still eventually dies and leaves me hanging. All I am doing is browsing with FireFox and reading email with Thunderbird (via IMAP). Simple stuff !!!
I've zapped Parameter RAM, disabled IPv6 for airport, and rebooted. Still no good. My access point is an Airport Extreme Base Station, configured in bridge mode, and connected to the Internet via an iinet ADSL router.

Out of curiosity, I tried another Mac Software Upgrade and it found an update to Airport Utility (v 5.5.1), so naturally I upgraded and ran AU. AU found my Airport Extreme Basestation and alerted me that there was a firmware upgrade available (7.5.1 from current 7.5). I've installed that.
Now lets see if things get better today and the next day. Surely couldn't get any worse .... could it ??

I'm using a BT HomeHub 2 and sometimes have an Airport Express unit plugged in, so this isn't a pure Airport Router problem. Tried changing the MTU to a lower setting (as recommended somewhere on the internet), but only succeeded in losing my Magic Mouse connection every few minutes! Have gone back to auto settings again for now.

My last connection did last for 18 hours before dying, so that wasn't too bad.