I am using Outlook 2007 with a POP account. When I look at the Calendar, days that do not not have anything scheduled are BOLDED. Days that do have something scheduled are not BOLDED. How can I reverse that? So days that do have events are BOLDED and days that do not, are just the normal font.

Did you try Help? I found this:

Turn Bolded Dates on or off:

1. In Calendar, on the View menu, point to Current View, and then click Customize Current View.
2. Click Other Settings
3. Under General settings, clear or select the Bolded dates in Dave Navigator represent days containing items check box.

Life is more painless for those who are brainless.

I did try help, I could not find anything. Perhaps the keywords I was using were not correct.
I did as you mentioned, still the same result. When I uncheck: BOLDED DATES IN DATE NAVIGATOR REPRESENT DAYS CONTAINING ITEMS. all dates are bolded.
Then When I check it again, goes back to bolding dates that has no appointments.

I did un-install Office 2007 and went back to Office 2003. Problem resolved. Dates that have events scheduled, are bolded.