Using Keychain First Aid
- Hit Command+Spacebar to bring up Spotlight, launch “Keychain Access”
- Pull down the “Keychain Access” menu and select “Keychain First Aid”
- Enter the password accompanying the given user name
- Check “Repair” and click on “Start”
If this doesn’t work then we can try removing the wireless networks from Keychain.
Remove Wireless Networks from Keychain
- Hit Command+Spacebar for Spotlight and search for “Keychain Access”, launch the app
- Using Keychain Access search box in the upper right corner, search for “Airport network password”
- Locate and select the name of the problematic router, if there are multiple entries for a single router select them all
- Right-click on the router name and choose “Delete RouterName”
- Authenticate the removal, then close out of Keychain Access
- Reboot the Mac and re-join the wireless network
Mac OS X should now remember the wifi password without incident.