I too only just began having issues with inability to save/efile on 7/25/23 (worked for me just a week ago). The File > Save As trick does work to get the file saved, but still unable to efile. Fortunately we have a Windows 10 workstation to utilize. I tried the Intuit workaround and that didn't do anything.

Though I'm curious what they mean by this piece (in red) of the instructions - how can I delete the selected printer within ProSeries, if that is in fact what they're instructing?

• Close ProSeries 2021
• Browse to C:\Prowin21\32bit
• Open Prowin21.ini in notepad
• Look for the following line under the [GlobalOptions] section
  • LetterInvoicePrinter=HP LaserJet 1022 Class Driver,winspool,LPT1:
  • This line will always start with LetterInvoicePrinter=, the rest will appear different depending on your selected printer
  • Delete this entire line
• Save and close the Prowin21.ini file
• Repeat the steps under Change Letter/Invoice Printer in ProSeries