String to Date Conversion

The custom number format section is to format dates. Excel does not recognize your string as date but as a text string, so in order to convert it to a date you'll need a formula. Once excel has a date; then you can use the custom format and show it whichever way you see fit. Hope this made it clear why you cannot format your text string.

Originally Posted by dasreinfeld

that makes sense now...could someone walk me through the steps necessary to make this happen?

Well, I'd insert a column after your date-text-string column and convert it to an excel proper date using DKO's formula above, copy this new column and paste values to your original column, and then delete this helper column.

Then you can use Custom format if you don't see an option under Date that satisfies your demands.