Compile Error: Can't find project or library (1 computer has the error, another does not?)

I have a request form that has been used by two departments for the past two years. After we went through an upgrade from Office 2007 to Office 2010, Department A is still able to use the form, while Department B receives the message "Compile Error: Can't find project or library". I have attached to this post a copy of the form, and a screenshot of the error being received by Department B. The form itself is much more complicated, but this is a simplified version that saves the PDF to your desktop so that it can be tested by anyone. If I can fix the error on this one, I should be able to incorporate the solution into the more complicated version.

Thanks in advance for any help that comes my way!

Screenshot of the Compile Error >>> Compile Error.jpg

Sub sendpdf01()

    Dim FileName As String
    Dim UserDesktop As String
    Dim WshShell As Object
    
      Set WshShell = CreateObject("WScript.Shell")
      
      UserDesktop = WshShell.SpecialFolders(4) & "\"
      
        FileName = Left(ActiveWorkbook.Name, Len(ActiveWorkbook.Name) - 5)
        ActiveSheet.ExportAsFixedFormat Type:=xlTypePDF, FileName:= _
           UserDesktop & Cells(2, 2).Value & " - " & Cells(6, 2).Value & ".pdf", _
            Quality:=xlQualityStandard, IncludeDocProperties:=True, IgnorePrintAreas _
            :=False, OpenAfterPublish:=False
        Range("A1:D28").Select
        
        MsgBox "This request has been saved to your desktop."
    
End Sub