ActiveSheet.Name not working?

I have set up a macro to print to PDF all sheets within a workbook (thanks to some input from this forum). It works on some workbooks, but tried running the macro today, and I got a message box that called the activesheet "working ", but not by the actual worksheet name. When I clicked "ok" to shut down the msgbox, I got a Run-time error '5', Invalid procedure call or argument.. Here is the code:

Sub SavePDFAllWorkSheet()
'
' SavePDFAllWorkSheet Macro
'

 Dim APath As String
 Dim s As Long
 Dim ASName As String
 
 
 APath = ActiveWorkbook.Path & "\"

 MsgBox APath
 
 For s = 1 To Sheets.Count
    Sheets(s).Activate
    
    ASName = ActiveSheet.Name
    
' this is where it said "Working" in the MsgBox

    MsgBox ASName
    
    ActiveSheet.ExportAsFixedFormat Type:=xlTypePDF, FileName:= _
        APath & ASName, Quality:= _
        xlQualityStandard, IncludeDocProperties:=True, IgnorePrintAreas:=False, _
        OpenAfterPublish:=False

Next
 
 
End Sub