Found one solution, see code below.
sFname = sPath & "\" & "0020-48183-fir_Cal-Precision.xls" 'Set File Name of Original file
vFname = sPath & "\" & "0020-48183-fir_Cal-Precision-" & sDcode & "-" & sScode & ".xls" 'Set new file name
'MsgBox sFname & " " & "Original file name" 'for testing
'MsgBox vFname & " " & "New file name" 'for testing
'Create new file name
'Check if exists, exit if exists 'need code
ActiveWorkbook.SaveCopyAs vFname 'NEW CODE
'MsgBox sFname & " " & "Original file should be open" 'for testing
This wasn't a matter of a macro not opening the original file, but the macro closing the file that did not need closing. Performing a "SaveAs" instead of a "SaveCopyAs" was closing the only excel file that was open. Allthough, I am not sure why I could not open a workbook after the close.
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