Add your own holidays and events to outlook calendar

1. On the Tools menu, click Options, and then click Calendar Options.
2. Under Calendar options, click Add Holidays.
3. Select the check box next to each country/region whose holidays you want to add to your calendar, and then click OK.
If you already added a country's or region's holidays to your calendar, the check box for that country/region is selected in the Add Holidays to Calendar dialog box. If you try to add the same items again, you receive the following message:
“Holidays for country/region are already installed. Do you want to install them again?”
If you click Yes, the holidays and events are installed a second time, and you see duplicate holiday and event entries.
In case if you accidentally clicked yes, here is the way to delete it.
1. Go Calendar, view, Current view, Events.
2. Select the holidays that you want to delete. To select multiple rows, press the CTRL key, and then click other rows.
**Click the Calendar icon to select a row. Do not click in the data cells of the row.
3. Click Delete on the Standard toolbar.
Create custom holiday and event files
1. Exit Outlook if it is running.
2. In Microsoft Windows Explorer, locate the following file:
C:\Program Files\Microsoft Office\Office12\1033
3. Make a backup copy of the file.
4. Open the Outlook.hol file , using a text editor .Example :Notepad
5. Type a new header and custom events by using the format described below
[Country or Description] ItemCount

Holiday or event description, yyyy/mm/dd

Note:
“ItemCount” is the total number of items listed for a particular country, region or description. There should be a space between the closing bracket and the number, as well as a carriage return at the end of the line. On each holiday line, there should be a comma and a space between the holiday description and the date, as well as a carriage return at the end of the line.



Example:
[Holidays] 4
sampleday1, 2009/06/15
sampleday2, 2009/10/03
sampleday3, 2009/12/08
sampleday3, 2009/04/14
6.Save and close Outlook.hol.
The next time you run Outlook, the new “Holidays” dates are available for adding to your calendar.