iMac returned from repair, now will not connect to WiFi?

[Mark Morb]

Hi,

My iMac has just been returned from being repaired, I had it for two weeks before sending it back. During that initial two weeks I had no issues at all with connecting to my WiFi network.
Now it has been returned, I turned it all on and it only sometimes even sees my network and will not connect to it even when it does..I'm getting "Time out" messages, sometimes it's asking for a key even though I have no security at all on my network (for various reasons).
My windows laptop still sees and connects fine, as does my Playstation3 and my girlfriends laptop...nothing has changed!! It's driving me mad....any suggestions???

It's a Netgear DG834G if that makes any difference....

 

[AndyK]

I have one of those routers and have that problem too, but for me just rebooting the router fixes it all.

 

[TMA]

So it's a brand new aluminium iMac? If it's only sometimes picking up nearby wireless networks it may be that they didn't connect the Airport antenna back up to the Airport card whilst it was in for service.

 

[Mark Morb]

It's very odd, sometimes it's not seeing any wireless networks at all (there are a couple that I can detect from neighbours).
I just moved the Router into the same room as the iMac and it saw the SSID, then it didn't, then it did!! But even when it saw it once I tried to connect it just sat there for a bit and then said "Connection Failed"
I connected to my neighbours network (he has no security either) and it connected fine!!!
But as I said, nothing has changed here and all my other WiFi devices (laptop/PS3/Nintendo DS/Squeezebox) are working fine.
iStumbler is seeing my network ok as well...54% Strength 13% noise.
I'm broadcasting on Channel 1 if that makes any difference...

 

[TMA]

Hmm so It doesn't sound like the card is at fault..

Have you tried going into System Preferences > Network > Airport > Advanced and deleting all the preferred networks? That should force your mac to make a new connection to the router as if it had discovered it for the first time.

 

[Mark Morb]

^^ Yes, I tried that. Got rid of everything, I even changed the SSID of my network and tried connecting to the new network, still wouldn't connect. I'm currently restoring my whole system to the Time Machine backup I had the day before sending it back, just in case "something" was altered whilst in the service centre.
Thanks for your suggestions so far....

 

[TMA]

It might be worth resetting and upgrading the firmware for your router before you resort to restoring your system, as I would say its 50/50 that would even fix it and it will take a lot of effort.

 

[Mark Morb]

^^ Tried that as well, it's quite an old Router (Nearly 4 years old). But the iMac worked straight out of the box no problem a few weeks back....it's only now after it's been returned

 

[TMA]

^^ Tried that as well, it's quite an old Router (Nearly 4 years old). But the iMac worked straight out of the box no problem a few weeks back....it's only now after it's been returned

That is a bit baffling then!

Have you tried making a new user account on your Mac and seeing if that works? If it does then you know its a software/config problem.

 

[ntrigue]

Go into your user folder and hit CMD + Shift + G and type ".ssh". Delete the known hosts file.

Or into Terminal enter:

rm -f ~/.ssh/known_hosts

Press Enter

 

[Reflow]

It's very odd, sometimes it's not seeing any wireless networks at all (there are a couple that I can detect from neighbours).
I just moved the Router into the same room as the iMac and it saw the SSID, then it didn't, then it did!! But even when it saw it once I tried to connect it just sat there for a bit and then said "Connection Failed"
I connected to my neighbours network (he has no security either) and it connected fine!!!
But as I said, nothing has changed here and all my other WiFi devices (laptop/PS3/Nintendo DS/Squeezebox) are working fine.
iStumbler is seeing my network ok as well...54% Strength 13% noise.
I'm broadcasting on Channel 1 if that makes any difference...

Give this a try. Change wireless channels on your router to see what happens. Also did you get anything new in the pass two weeks like a new cordless phone or anything electronic?

 

[BaronvdB]

i feel your pain...my internal mic got broken the last time my imac was in for repair on something else...very annoying.

 

[Mark Morb]

Thanks for all the above suggestions. The Time Machine restore to the day before it went in for repair has sorted it out. They must have altered something during the repair procedure.
As soon as the mac rebooted from the restored system it found my WifI network and connected immediately...

The fact that the reason it went in for repair does not appear to have been addressed is another issue altogether

EDIT: Spoke to soon, it is now randomly seeing and/or connecting to WiFi networks again....

 

[TMA]

Sorry to hear it's still not working.

On a slight side note, I used to have a Netgear DG834G (one of the older revisions) and found that it had appalling wireless performance in regards to speed. I could connect to it fine, but even when it was in 802.11g mode only, I would get an absolute maximum throughput of 2mbit/sec. I switched to a Belkin unit which provided more than enough speed to cope with my 8mbit/sec broadband line.

I still wonder if your problem is hardware related, a cable that wasn't re-connected probably or has been routed along a circuit that is causing interference.

 

[Sirus The Virus]

My old router was a Netgear, I don't remember the model though... But I was having issues connecting with WiFi, so I bought a new router, and it solved all my problems.

 

[Mark Morb]

I'm beginning to think I should update the Netgear, it is a bit long in the tooth now.

Any good suggestions as to a good curernt Wireless Router/ADSL Modem?

Thanks,
Mark Morb