External disk unmounts and mounts without reason

Number:rdar://9727925 Date Originated:july 6, 2011
Status:Closed Resolved:No
Product:Mac OS X Product Version:10.7.0
Classification:Crash/Hang/Data Loss Reproducible:Yes
Summary: Once I upgraded to Lion, my external disk (named Annex) randomly unmounts and then within a minute, mounts again through no action of my own. I see a "The Disk was not ejected property" dialog (attached) when this happens, iPhoto 9.1.3 says my library is unavailable if it is open when this happens.

Steps to Reproduce:
I can't list any because I don't knowingly do anything to cause this situation to happen.

Expected Results:
External disk randomly powers down, unmounts, then seconds later remounts

Actual Results:
External disk stays mounted until the user unmounts the drive.

Never happened in Snow Leopard from 10.6.0 to 10.6.8


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