Downloads: Acrobat reports, "There was an error opening this document. File does not begin with '%PDF-'".
Did you first unZip the file? You will get that error message if Acrobat is being asked to open a file type other than PDF. So, if the file you are attempting to open with Acrobat is named, for example, "calling_d.zip", then the file has not yet been unZipped, and you need to unZip the file with either the Windows file manager or a separate utility (see below).
If the file is indeed named "calling_d.pdf", and still won't open, then it is possible you are using an older version of Adobe Acrobat, or Reader. You must use version 4.0 or later; for more recent versions of our devotionals and drama scripts, use version 6.x. For best results, download the latest (free) version of the Acrobat Reader.