Selected Answer
Hello RWSM,
I'm guessing that the worksheet after "Project Codes" changes or you would have simply inserted that sheet name in your code. You need to use the index number of "Project Codes". A sheet's index number refers to its placement in the workbook, the order across the bottom of the workbook. To open the worksheet after "Project Codes" use this:
Private Sub Workbook_Open()
Dim IndexNbrA As Long
IndexNbrA = Sheets("Project Codes").Index
Worksheets(IndexNbrA + 1).Activate
End Sub
If this solves you problem, please mark my answer as Selected
Cheers :-)