Launch Applications -> Utilities -> ColorSync Utility and select Repair from the Profile First Aid tab. This will repair any ColorSync ICC Profiles with errors. I haven't done much with ColorSync but it found some errors and repaired them.
[robg adds: I've done almost nothing with ColorSync other than set my monitor, and the repair function found 20 (and fixed 19) profiles with problems. Most of these were system-supplied profiles, so I guess I'm curious as to how they could be damaged when they are basically as-shipped? In addition, one profile (/Library -> ColorSync -> Profiles -> 150-Line (Pantone)) couldn't be repaired at all...]
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