Can't call method "Workbooks" on unblessed reference

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my $book = $Excel->Workbooks->Open( $excel_template ) or die ; # open 
+Excel file
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The code posted is trying to run the Workbooks method of the $Excel variable. In Object-Oriented speak a "method" is a subroutine tied to an object or class.

To get started with objects in perl see bless, perltoot, and perlobj.