You should still be able to upgrade from Windows 7 or 8.1 to 10 for free. Visit this page and download the media creation tool. Use the media creation tool to upgrade to Windows 10. If asked, make sure the keep my files and apps option is selected. Once Windows 10 is installed and you are connected to the internet, verify that Windows 10 is activated. Great, thanks for your reply.
I purchased the 3542 with Windows 8.1, and now would like to upgrade the OS. I see from a few posts that I can't upgrade to Windows 11 - [URL]  and  [URL]   Can I upgrade to Windows 10 or even Windows 10 pro ?  Is the upgrade available as a purchase from Dell Australia please ?  
Inspiron 3542 - Can I upgrade to Windows 10 ?