Wireless losing internet connection but still connected to router?

Hi,

I have a 2011 iMac 27" which is connected to a BTHUB3 wireless router.
For some reason without warning (and it happens multiple times a day) my connection stops and no web pages will load.
If I hover over the wireless network icon on my mac to show wireless devices in range etc it shows that I am still connected to the router but nothing will load.
What is even stranger is if I hover long enough for it to refresh my wireless router pops up a 2nd time so I then have the same router showing in the list?

The only way I can get the internet to work again when this happens is to switch off my airport and switch it back on again then all is well....until the next time!!!

Any ideas please? It's driving me mad.

What version of of OS X are you using? There was an issue with Lion and Wireless dealing with not connecting after coming out of sleep. But this didn't affect ongoing use when the iMac was awake..

Hi,

I am on OS X

10.6.8

OK a few things to try:
- Re-install the .8 update to Snow Leopard using the Combo Updater.
- Reset the SMC

If you check Network Preferences and if you have a Self Assigned IP address rather than a valid IP address, then you try deleting the file com.apple.alf.plist from the /Library/Preferences/ folder..

If you're staying connected to the router it may be the router losing connection to your ADSL line.

After a disconnect log into the BT Hub and in advanced check the logs and see how long the ADSL connection has been connected.

Upgrading the OS seems to have done the job thanks.

I did not do anything with the SMC or or IP.

Many thanks for the responses.