Since Installing Windows 10, I cannot edit PDF files such as the 941 Form.

Yes this is a Windows 10 problem, Windows 10's installation will steal the file association from Adobe Acrobat and switch it to the new Microsoft Edge browser. So the PDF files are no longer opened in Adobe Acrobat and Edge cannot edit them.

You have two choices to fix the problem...

You can save the file and then start Adobe Acrobat and open the saved PDF file. Or the best way is to click the Start Menu; Settings; System; Default Apps; and then Choose default apps by file type. Scroll down to .pdf and set it to use Adobe Acrobat. See this PDF File fpr details with pictures:

[url]https://zpay.com/pdf-files/Set-the-PDF-Files-to-Adobe-Acrobat-Win10.pdf[/url]

Since the above was posted, we've discovered another PDF program being installed on Windows 10 computers called Adobe Touch Reader is blocking PayWindow from creating the PDF files for the 941 and other forms. Uninstall that Adobe Touch Reader and install the Adobe Acrobat Reader from Adobe.