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#11
Sorry I don't understand the relevance of the .PNG file? You said you tried this once which is not related here as far as I can tell?
At this time you want to use a transparent .ICO file as the icon for your folder- yes?
Is this happening with any other icons other than for the folder you have mentioned?
Try rebuilding the icon cache again as suggested above.
Then restart Explorer *cleanly* by typing TSKILL EXPLORER in the Start/Search box and hit Enter.
Additionally flush the Thumbnail Cache also. You can do this via CCleaner if you have or follow this forum tutorial...
Thumbnail Cache - Clear and Reset
Again restart Explorer *cleanly* as before.
Reboot and test???