The "gray" area is the displayed portion of your current view setting. Meaning you are looking at a 7 day week, and those 7 days show as a grayed area. If you were viewing a day, then just a single day is grayed. If you were viewing a month, then you'd see that month as a gray area.
The days that you have something scheduled will display as a bold date. The bolding is difficult to notice in the gray area, but it is there.
Your October 10 appears to be bolded.
Running Windows XP Pro SP2, with MS Office 2002 Pro.
I am a new user of Outlook. My little annoyance:
With MS Outlook opened in Calander (5-day week), I notice that on the right the clanader for October have the dates from 10th to 16th blank. I have a calander entry for 10th October. Why are the dates blank ? the row of dated is blank, not greyed out. This only happens sometimes.
Screenshot. Thanks for any responses.
christy

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic