In Online Office, you can open files from your mail.com
File Storage or upload locally stored files from your computer.
Please note that only the following file formats are supported: .doc, .docx, .odt, .rtf, .txt, .ppt, .pptx, .odp, .xls, .xslx,
You can upload locally stored files from your computer to view and edit them in Online Office.
You can open files that are saved in your File Storage in Online Office to view and edit them.