Compare two columns for missing values in Excel

At work this morning, I had to make a list of managed computers with 32-bit operating systems which were not checking into a console. In this article from ExtendOffice, they walked through the process of comparing two columns for duplicate data by using a formula in the third column.

Once I had the formula 1 in place, I formatted the data as a table. Clicking the third column’s header provided the option to uncheck “Select All”, then scroll down and select (Blanks). The resulting view showed the items missing from my list.


  1.  =IF(ISERROR(VLOOKUP(A3,Sheet2!$A$2:$A$22,1,FALSE)),A3,””)