I Cannot Open Attachment Files

Filename Extensions

If your computer has a older version Microsoft Office (prior to 2007), you'll need to download software called "Microsoft Office Compatibility Pack" in order to view files created with newer versions. Please read this for more information.

Download Link
Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint File Formats

After the file downloads, close all Microsoft Office programs, then install the file. After that, reboot Microsoft Office, and you should be able open docx, xlsx, pptx files.