Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hi Jack,
In regards to your concern, Microsoft Office uses the XML-based file formats, such as**.** docx,. xlsx, and . pptx, since 2007 release. These formats and file name extensions apply to Officeapps Word, Excel and PowerPoint.
To learn how to open the files in that format, you can refer to this link.
Should you need further assistance, feel free to reply on this post.