MacAir not detecting external monitor. 'check signal cable' error

Brand new MacAir OX 10.7.4 not detecting samsung external monitor. I keep getting 'check signal cable' error on a blank screen.

Hi Walter,
I'm not sure this'll fix your problem, & it's info from earlier OSX versions, but I'll toss it out...
Safe Boot from the HD, (holding Shift key down at bootup), run Disk Utility in Applications>Utilities, then highlight your drive, click on Repair Permissions...
Trash these files...
/Users/YourUserName/Library/Preferences/ByHost /com.apple.windowserver.<12digitHex#>.plist
/Users/YourUserName/Library/Preferences/ByHost/.GlobalPreferences.<12digitHex#>. plist
There may be more than one of each of the above, then trash...
/Users/YourUserName/Library/Preferences/com.apple.systempreferences.plist
Reboot
You could test it by first, depending on OS version...
To find out if it's system wide or user specific, try this...
Open System Preferences>Accounts, unlock the lock, click on the little plus icon, make a new admin account, log out & into the new account.
Does it work in the new account?
To find out if it's system wide or user specific, try this...
Open System Preferences>Users & Groups, unlock the lock, click on the little plus icon, make a new admin account, log out & into the new account.
Does it work in the new account?

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