To export the birthdays of all contacts from contact folder in Outlook, please do as follows：

1. In the People (or Contacts) folder, select the contact folder that you will export contact birthdays from, and then click View > Change View > List to show the contacts in list view.

2. Go ahead to click View > Add Columns. See screenshot:

3. Now the Show Columns dialog box opens, please (1) select All Contacts fields from the Select available columns from drop down list; (2) click to select Birthday in the Available columns list box, and (3) click the Add button. See screenshot:

Now the Birthday column is added into the Show these columns in this order list box.

4. Go ahead to remove unnecessary columns from the Show these columns in this order list box, and click the OK button.

Note: You can remove unnecessary columns as follows: (1) select one of unnecessary column in the Show these columns in this order list box, (2) click the Remove button, and (3) repeat to remove other columns.

5. Now you return to the contact folder, press Ctrl + A keys together to select all contacts in it, and then press Ctrl + C keys simultaneously to copy them.

6. Launch Excel, select a blank cell, press Ctrl + V keys together to paste the contacts, and then save the workbook.

So far, the birthdays of all contacts have been exported from the specified contact folder in Outlook already.

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