Before I buy airport I want to make sure that is will make my imac fully wireless, with no ethernet connections. Is this the case?
Yes, assuming that your iMac has a wireless card installed and it is operating correctly....and the iMac is located where it can receive a strong wireless signal from the AirPort router.
Might be a good idea to test that iMac out first.
When I hit the button up right it says no airport card installed. Now what?
Depending on the model of your iMac, you would either need to install an AirPort Extreme card inside it or use a wireless USB adapter. This would allow your iMac to join existing wireless networks.
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