Dean,
It depends a bit on what you mean by a PAfE file since there are several different types of reports that you can create in PAfE. For example, if you're using explorations or quick reports you'll find a bunch of properties in Sheet.CustomProperties that you can key off of to know there's PAfE data on that sheet. If however you're using Custom or Dynamic Reports then those are entirely formula based and you can't count on anything special in the worksheet properties. For these types of reports you'll need to use Excel's SpecialCells find feature to try and find a formula that is a DBRW (presumably).
As an alternative to automating PAfE through VBA we have a product called ReportWORQ that can refresh PAfE workbooks in bulk and in the background. There is a free trial if you're interested in this route:
http://quebit.com/rwThank You,
Andy Weiss
QueBIT
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Andrew Weiss
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