Mac OS X Snow Leopard: Why does my wifi icon have an exclamation mark?

Hi, I have the same issue with the exclamation mark on the wireless icon on snow leopard however I did notice the alert no internet connection once you click on the wireless icon.

The strange thing is that I am still able to use the internet and it does not have the exclamation mark at home, only in my University campus. As I say the internet is working but the exclamation mark remains. My university has no idea and have confirmed that is is only with snow leopard macbooks. This did not appear on the icon until I upgraded to snow leopard.

Any ideas? Thanks!

this problem persists in my iMac as well, i've tried configuring it but have no idea how to get the internet to work on it. we have other wireless devices using the same internet modem but my iMac (using snow leopard) still has the exclamation point.

is there a way to reset or reformat the wifi so that this goes away and i'm able to use the internet?

I've had the same problem since upgrading to Snow Leopard. When I try and join certain networks, I get the exclamation mark over the airport icon and no connection. It does this with one of my home routers (which my girlfriend's MacBook connects to fine) and now my office network too. So now I'm screwed! Is there a cure?

So...i just had this problem. I am at a coffee shop where I have connected 100s of times on my old macbook (not snow leopard), and this guy with an ancient macbook behind me connected fine. After cursing my computer and getting quite upset. I fixes it by closing my computer and then opening it. That just doesn't seem right that a brand new computer would be doing that. Hmmmm. Any suggestions on how to make it not happen again?

I had this problem, too (the exclamation point over the airport symbol). After speaking with the IT manager at the office where I had the problem, I learned that that office had changed their password or entry key for wireless connection. Upon entering it, problem solved. My problem was that I was still using their old entry key and was not told that it had been changed.

Stephanie, it is not for us mortals to understand the mysterious ways of our Mac systems, just to sacrifice our greenbacks and pray that they'll work properly. :-)

Seriously, sometimes the wifi software gets into a weird state and takes a while to make the appropriate handshake with the base unit or server. Sometimes I find that turning Wifi off, waiting a few seconds, and turning it on again helps too.

I went crazy with this ... apparently I was connected with a wrong password to the wifi!

I couldn't believe it .... after spending hours trying to fix this and checking the internet forums I logged in the router and noticed that the password was 0966232983 but I had entered with 1966232983.

I still don't know why it let me enter the wifi network with the wrong password!

I tried put an 0x in front of my password (I have a WEP protected router) and instantly it worked when nothing else did. I had tried turning air port on and off, resetting the router, changing my IP address and configuring everything manually, deleting certain suggested files in my system configuration, still no internet connection.

Wow, I've had this problem for so long... I just tried to put an 0x in front of the password, and now it works!!!!
How on earth!??!?!
Thankyou so much, Beth!

Oh. My. God. I have been driving myself completely insane for the last six days straight trying to get that stupid exclamation point to go away and I just tried that 0x trick and IT WORKED!!!!! I'm beside myself with joy. My sanity can return! Thank you thank you thank you!!!!!

Thanks for the 0x tip. That's what did the trick. How did you come up with that? Talk about random.

i tried doing this but it didnt work. any other ideas?

That is the weirdest solution... and I'm so HAPPY (and stunned) that IT WORKED!!! Thank you for the simple and highly effective answer to a very vexing problem.
Just entered the "0x" before the other characters of my password (on WEP protected router) and it started working right away. I don't know why it works... but it does.
BTW (I'm running Snow Leopard version 10.6.1)

Can't believe it, but after a month and finally finding this forum I got my wife's computer working again!!!
whoever figured out the voodoo trick "0x" just saved me from buying a new router or computer!

OK, so my MacBook's connection suddenly stopped working yesterday, and still has the exclamation point over the airport. It's the only Mac computer ever used in my house, and every other computer that uses wireless, and my brother's iPod touch, work fine on the connection (I've resorted to using this foreign DELL to try to fix my problem). I've tried the "Ox" trick, tried renewing my DHCP lease, everything I can find I've tried, but nothing works

In System Preferences>Network, in the AirPort tab under status, the message reads: "AirPort has the self-assigned IP address xxx.xxx.xx.xxx and will not be able to connect to the internet"

Does this mean I have to somehow change my IP address? If so, how do I do this?

Thanks in advance to anyone who can help.

Dave is being a little condescending isnt he? not only that - but he's got it wrong... We all of us with this problem have an issue with the Fan signals strength icon which starts up (in my case) fully filled (Black) and then goes grey (not signal) and has an exclamation mark through it. Looking at all the posts it seems to be something with the security. The wifi router in our home is working perfectly with the other three computers we use (two IMacs and a PC) but not with my brand new Snow Leopard based Air. However I've tried working with the Air's airport crypto settings and that hasn't worked. And it works fine everywhere else in Europe but here - which may have something to do with the way that the local provider configures their routers..

Anybody got any advice to someone who learned how to spell computer forty years ago and has used Mac as his work tool since 1987? In other words: 'I've plugged it in properly -what next?'.

The 0x tip worked for me. GREAT tip!

I have NEVER posted in a forum in my life but, I tried the 0x and it worked.

Apple genius bar and Apple Care... waste of space.

Whoever started the 0x thread in here - bravo!

OMFG i really want to thank who ever came up with this EPIC idea to put and 0x infront. thanks so much for relieving my stress over the few days :)

Same problem with the exclamation point, but with a twist.

Upgraded aging MacBook to 10.6, which now looks like a mistake. Cannot connect wirelessly, but the ethernet cable connects fine. Tried everything: restarting, editing locations, updating router's firmware (US Robotics 9110), running airport utility, renewing DHCP lease. BTW, there is no network password; our wireless is fully open.

The twist is, when I plug the ethernet cable in, the wireless indicator has a full fan of bars. When I unplug the cable, the exclamation mark reappears and no wireless connection.

Thinking about going back to 10.4.

the 0x method works like a charm. ive been having the exclamation mark problem for months now and for that i havent been using my mac much. i just entered 0x into the passoword section for that connection and it immediately connected like magic. THANKS LOADS!

Does anyone have any idea what a gray wifi symbol with what looks like a blank computer screen on it, might mean? My laptop is working fine with my wifi, but the desktop is not working at all. Very confusing. Thanks for your help.

Hope that's helpful...no, not really...links to help would be nice.

Has anyone had the exclamation point problem, and then been connected to another unfamiliar network?

I just recently moved, and am not using my router, I'm using my roommates. I notice when I get the exclamation point, I still have the net, but I seem to be connected to a network that I don't know, have never been on, and is password protected. Is it possible I'm getting hacked? Oh yeah, and I'm on 10.7.2.

I have had the exclamation point issue for MONTHS now. Tried different routers, called my ISP, nothing worked. But the 0x thing did. Whoever did this, you are a genius!

I had the same problem and I just turned my modem off and then turned it back on and it got the connection. Hopefully this helps for some. This happened in my house.