If your computer is displaying appointments and/or slots off by an hour, the first thing you should check is the time zone setting for your computer. From your Control Panel, select "Clock, Language, and Region" then select "Date and Time." This displays the time zone set for the computer, make sure it is the correct time zone for your region. If your calendar events are only off during daylight saving time, you may have the correct time zone but your computer is not set up to recognize daylight saving time. Click 'Change time zone...' and verify the checkbox for "Automatically adjust clock for daylight saving time" is checked.