How to add a user defined formula filed in Outlook Inbox folder?

To calculate how long you have received emails in the Inbox, please add a user defined formula field with following steps:

1. Click to open the Inbox folder, and click View > Add Columns. See screenshot:

2. In the Show Columns dialog box, please click the New Column button. See screenshot:

3. In the popping out New Column dialog box, please (1) name the new column in the Name box, (2) select Formula from the Type drop down list, (3) click the Edit button; (4) type the following formula in the Formula Field dialog box, (5) and finally click OK buttons successively. See screenshot:

DateValue (Now())-DateValue ([Received]) & " day(s) ago"

Notes:
(1) You can paste the formula into the Formula box of the New Column dialog box directly;
(2) You can find out many Outlook formulas in the Function drop down list in the Formula Field dialog box. See screenshot:

4. Now you return to the Show Columns dialog box, please keep the new formula column selected in the Show these columns in this order list box, click the Move Up or Move Down buttons to adjust its order, and click the OK button.

5. Go ahead to turn off the Reading Pane with clicking View > Reading Pane > Off. See screenshot:

So far, the specified user defined formula field has been added in the Inbox folder, and showed the received time as x days ago. See screenshot:

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