Vanishing files in Finder
When I search my USB drive for documents modified in the last 7 days to backup the Finder window lists the correct files but then the list disappears off the top of the window, then reappears, then disappears and this continues not giving me the opportunity to select the files to copy to my backup disk.
How do I stop the list of files disappearing ?
iMac (27-inch, Late 2012), OS X Mavericks (10.9.1)