Four Way to Fix Error 0x80070021

I've been facing the "Error 0x80070021" when attempting to back up my Outlook PST files, and I've read through Yousuf Hasan's article:  Error 0x80070021 in Outlook. The article provided four reliable solutions. However,  I'm also curious if anyone has tried other methods to fix this error.

Has anyone used different tools or approaches? I'm not against trying the methods mentioned in the article, but I'd like to explore multiple options before making any changes to my Outlook setup. Any advice or suggestions would be greatly appreciated!