Dell Studio 1558, Win 7 Pro X64. Start > Sleep. Press power button to come out of sleep. 3 out of the last 5 times the laptop comes back with a message that Windows was not shut down properly etc. I looked in the System events log and found that every time I put the computer to sleep an error message is logged when I have the computer come back from it (even in the cases where there is no message on the screen stating that Windows was not shut down properly). The error message in the System log is the usual "The last shutdown at (time/date) was unexpected".