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OS 10.5.8 imac 300 gb 4gb ram.. It seems that everything I click on becomes surrounded by a thin walled black rectangle. Even the HD icon the desktop has one until I open up something else. I cannot figure out why. The subject box above had one until I started to type here below and then this window has one.
Can someone help me out here? I've just noticed that when I scroll up, the rectangle remains where it is.

jaybass