Try this array* formula:

=SUM(IF((B1:B500="Indiana/01")*(D1:D500="enroll"),1,0))

* As this is an array formula, once you have typed it in (or
subsequently edit it) you need to use CTRL-SHIFT-ENTER instead of just
ENTER. If you do this correctly, then Excel will wrap curly braces { }
around the formula - you must not type these yourself.

I have assumed the data is in rows 1 to 500 - adjust to suit.

Hope this helps.

Pete