Gmail supports compressed folders like zip ... can download the folder by clicking on the link. You can send large files via Google Drive. Go to Googe Drive and click on “My Drive > Upload ...

Now go create a folder (I created a “Files” one on my desktop ... I can access my files by simply logging in Gmail. Plus, it takes a drag & drop to send a file over. If you have tips and suggestions, ...

When your pending emails are sent, your Outbox folder shows the message ... like stuck emails in your Gmail outbox. Clearing your cache doesn't delete files that are necessary to run the app.