Is this excel expression correct countif mail.com d2

A simple one!

The expression COUNTIF(mail.com, D2) is not correct.

The COUNTIF function requires two arguments:

  1. The range or array to search
  2. The criteria to apply to the search

In your expression, mail.com is not a range or array, it's a string. You probably meant to use a range of cells that contain email addresses, or a specific cell that contains an email address.

If you want to count the number of cells in column D that contain the string "mail.com", you can use the following expression:

=COUNTIF(D:D, "*mail.com*")

This will count all cells in column D that contain the string "mail.com" anywhere in the cell.

If you want to count the number of cells in column D that contain a specific email address, say in cell D2, you can use:

=COUNTIF(D:D, D2)

This will count all cells in column D that match the value in cell D2.

Let me know if you have any further questions!