For attaching multiple files to an email, another possibility is to compress the files into an archive (ZIP, RAR, 7Z, GZ, BZ2, etc.). But, that topic is best discussed in a separate article.

To attach a folder to an Email, in Outlook, Hotmail, Gmail, Yahoo, or any other email service provider, you can use this trick.

You can send a zip file in Gmail if you want to send a large file or folder to someone without using Google Drive. Gmail has a hard 25 MB limit for sending attachments over email, and if you try ...

You can attach a folder to an email in Microsoft Outlook to send several files all at once by compressing the folder into a zip file.

When I try to attach one to an outbound e-mail, Outlook displays everything in the selected folder except Zip files.