grey boxes and black bars?
Repairing permissions, especially on a daily basis, really does not do anything.
If you are getting the problem in a Web Browser window, Safari or such, then you may have installed an Ad-Blocker which is displaying where the Ad was.
Have you installed anything like that lately?
P
Not sure if this started after downloading Yosemite , but I keep getting grey boxes and black bars appearing and flashing. I was told it was permissions , and I verify and repair almost every other day.Help?????

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