For a year or more, I've been having trouble with application icons frequently not copying when I copy a file from one folder to another in the Finder. I would get a generic icon on the copied file, and have to copy and paste the icon from the original to the copy. The problem persisted after I upgraded to Snow Leopard. I concluded that it was an incurable Finder bug -- no amount of system maintenance would fix it.
Then I found a little free app, Refresh Finder, that solved the problem (there are a few other apps that do the same thing). Rather than restarting the Finder, these apps just refresh the window, and the icons appear as they should on recently-copied files.
As it happens, this window refresh issue has been around for a long time; other manifestations include files moved or copied or downloaded to a folder not showing up. I guess I was just being dense, but I didn't connect the two (mis)behaviors. But they are, it seems, one and the same problem. Anyway, you can drag and drop the Refresh Finder app to the Finder's tool bar to have it handy in every window; just click on it whenever either of these window refresh problems occurs. For me, it is a simple and welcome solution to a vexing problem.
[robg adds: Macworld's Dan Frakes covered Refresh Finder as a Macworld Gems entry a couple years back. As Dan explains in his article, Refresh Finder is a front end to a relatively simple AppleScript:
If you're running Snow Leopard, create a new Service in Automator, set it to work in Finder (receives no input), and then add the Run AppleScript action to your Service. Save your Service, and you can then (using the Keyboard Shortcuts tab of the Keyboard System Preferences panel) assign it a keyboard shortcut. Now you can refresh a Finder window via the keyboard.]
tell application "Finder" tell front window update every item with necessity end tell end tell
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