SUMIF Closed Workbook Issue #Value! Error Message

[freckles527]

I have the following formula that works when both workbooks are open, but not when the one I'm pulling from is closed. This is a report for another team that won't be opening the workbook I'm pulling from. I've read to use SUMPRODUCT for closed workbooks, but struggling on writing it correctly to work. Any help would be greatly appreciate it.

=COUNTIFS('N:\External Audit\AUIDT TRACKER\[FINDING TRACKER 2017.xlsx]Findings'!$AN$2:$AN$10000,"=7/3/2018")