The main problem is that you're not specifying the file type when you save it; merely adding a PDF extension does not a PDF make. Your code could also be greatly simplified. Try:
Code:
Sub SaveDocument()
' this program saves the document in the Suntax Uploads folder on the user's desktop
Dim rng_claimant_id As Range, str_claimant_id As String
With ActiveDocument
Set rng_claimant_id = .Range(Start:=ActiveDocument.Words(1).Start, End:=ActiveDocument.Words(1).End)
str_claimant_id = Left(rng_claimant_id, Len(rng_claimant_id) - 1)
.SaveAs2 FileName:="C:\Users\" & Environ("Username") & "\Desktop\Suntax Uploads\" & _
str_claimant_id & ".pdf", Fileformat:=wdFormatPDF
End With
End Sub
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