I have just installed mountain lion.
All went good, but now i have à problem with wifi.
My connection is ok, i get an ip adress, but i cant get On internet.
Safari says it has no internet connection.
When i connect on ethernet i have internet.
Do anyone know what The problem is?
MacBook Pro, OS X Mountain Lion
I have the same exact issue. 😟
Please help. I tried everything. I found these but to no avail. still cant connect.
Fix #1: Add a New Network Location & Renew DHCP
This may work best for those who upgraded from a previous version of OS X to Mountain Lion but if you’re having the wifi drop issue go ahead and do it anyway because it is consistently successful with addressing wireless issues:
Your wireless connection may now be active and working fine, but renew the DHCP lease anyway:
The network location and DHCP renewal tip resolved similar wifi problems in Lion, and it seems to work in Mountain Lion too for many users.
Fix #2: Change MTU Size to Prevent Dropped Connections
This is a bit geeky but bare with us: MTU stands for Maximum Transmission Unit and controls the largest packet size allowed for transmission over the network. If this setting is greater than network capacity, the computer will experience packet loss and dropped connections. The default setting of 1500 is somewhat aggressive and some networks reject packets of that size, but it turns out that 1453 is just small enough to maintain a consistent connection with most networks but just large enough to not cause any slowdowns, it’s the magic number and an old cisco networking secret.
Be sure you’re joined on a wireless network, close out of System Preferences, and enjoy the internet as usual.
With all due respect, this is not the problem we are talking about here. This thread is about certain Mac computers (more specific the newer iMacs) that are not able to maintain a stable WiFi-connection to any brand of router, not Apple-routers specifically.
You are right that this problem started with the introduction of Lion/Mountain Lion on those iMacs. It has existed ever since, also with 10.8.2 and 10.8.3.
AppleCare replaced the WiFi-card inside my iMac, the result was exactly the same problem. I was able to resolve this issue by following the advice of the manufacturer of my modem/router: 'switch off radio channels 12 and 13 and deactivate channels optimized for 300 Mbit/s, as these are not handled very well by certain WLAN adapters'. See my posting dd 14 mar 2013.
After installing Mountain Lion I was unable to access the internet over Ethernet or WiFI - I think this was a problem with my Netgear Router configuration (nothing to do with the iMac)
Previously I'd assigned the iMac a fixed IP address in the router's LAN setup page.
After installing Mountain Lion, the router didn't recognize the device (even after numerous reboots of both devices)
Deleting the iMac from the router's LAN setup page fixed the issue for me. I set the the iMac Networking settings to automatic / DCHP and all was OK
I have a MacBookPro / Mountain Lion with Xfinity Comcast - WI-FI was connected but no Internet. Was driving me crazy and FINALLY FOUND THE SOLUTION!!! Went into the router settings and changes the channel to channel 11. YAY!!! Works great.
After Months and Months of waiting for Apple to role out with an update and not doing so, I became very frustrated. But, I have finally found the Solution! The wifi problem is a defect in the software, and for those of us who own an iPhone, we know all about restoring the software. Essentially, you must do the same thing to your mac (re-install the OS). To do so, follow the steps on ths website: http://www.dummies.com/how-to/content/how-to-install-or-reinstall-mac-os-x-mount ain-lion.html
This will delete the defective software, and reinstall a fresh, new software. You will not lose anything on your mac during the process.
I have already tried that, hasn't worked for me.
Also backing up to USB drive instead of Time Capsule only reduces the drops. I noticed that as soon as I want to sync my iPhone over Wifi the connection fails immediately. Really weird.
Sorry for your wifi troubles. I was having troubles too and finaly realized if I changed the channel of my router (which I did - changed it from 1 to 11) maybe it would work and to my delight it works like a charm....no more wifi troubles, this was a few weeks ago.
Actually I had already tried that, forcing the use of channel #11 but it doesn't fix the problem permanently. It still occurs, from time to time, that I need to try for two or three mintues to get a connection to the Airport router.
That didn't do it for me, but it looks like I solved the problem by connecting to the Time Capsule 5 GHz explicitly. Time Machine Backups, iPhone iTunes Sync, everything works flawlessly now!
As soon as I connect to the non-5GHz-Network the drops occur again! Haven't read this tip anywhere, I hope it might work for some of you too!
Got it working a long time ago - don't know why or how. Then I bought a new TV and it would not connect to WiFi. I then set my airport to a non secure protocol and got my TV connected. Swiched back to WPA2- personal. Great!
No :-( WiFi still works with the TV, but my MacPro pretends it's at a new home everytime.
Now - whenever my mac slumbers or I restart, I have to connect manually. In settings it tells me that my network is open, even though its WPA2. Apple please fix. NOW!!!
Constant network problems since 10.8.3 upgrade. I have gone through all the usual things. Power options. Raised everything up high as far as screen savers, and power options.
STILL NOT WORKING.
I would like apple to
A. PROVIDE A **** FIX fot this
B. Give me my money back.
Example. Each time I want to connect from one IMAC to another IMAC in my same house. I have to go into finder and click on the computer I want to connect to, to wake the God **** thing up. Half of the time, this doesn't work.
Then I try to ping the god **** thing and It's basically dead, till I physically go to the IMAC and move the mouse to wake the piece of crap up. I am going to contact the BBB as well as the attorney general and whoever I need to, to get my money back or get this fixed. Tired of this crap.
IT'S 2013 APPLE. WAKE UP
If you are trying to tell me the fix is in this thread point it out to me? Ii must be the one thing I haven't tried since the problem started with Lion.
If you work for Apple I'll give you the names of the Apple Engineers that have phoned me about this issue and you can tell them the fix so they can send it to me and all the other.
Obviously they missed it too!
Oh thanks for that important and very useful reply, that just might have fixed my wifi!
You already stated you don't work for Apple, you don't believe me and you have nothing useful to contribute to solve my issue. Why is it you are here?
Yes I am here complaining and so is every one else who has a wifi issue. I know some of you don't believe me that I have worked with Apple on my issue, fine. But lay off me. What difference does it make to you.
If anyone has a true fix post it.
That is all I'm asking.
Please, pretty please.
I'm sorry for being upset. It's only wifi.
OK.
What have you tried so far, have you made a new WiFi connector or a new location? Have you reset the router or changed security levels. Have you run without security as a test.
There are more things but I want to get some idea of where we are right now.
Where are we? I'll tell you where we are. We're nearly a year on, Mountain Lion has been updated to 10.8.3, and we still have the problem, and Apple (as far as I can tell) has yet to acknowledge that it even is a problem.
I have tried the following:
* Making new connection
* Making new location
* Deleted wifi keychains
* Changing router to WPA2 security
* Changing router altogether!
* Tried Snow Leopard driver
All of which leads me to think that it's the hardware that is at fault - which would explain quite neatly why Apple haven't acknowledged the fault!
Mountain lion wifi problems
