With Mac OS X Yosemite was also the Mail App revised. Lately you can with the help of Mail Drop very large files to send. Assuming you use iCloud. Many providers set like a maximum limit on how large a file attachment may be you want to send. With the use of Mail Drop eliminates this limitation practically. Here are the instructions.
Who the iCloud service, can now with the Mail App from Apple attachments send up to 5 gigabytes in size. If such a Mail is sent, the attached file automatically to iCloud, loaded. Recipient of the Mail, the Mail App use the Apple, will receive the attachment as usual. All other users, a different email Client or use Webmail, to receive a Link, via which the attachment to the email can download. Mail Drop should with any E-Mail service to work.
Tutorial for Mail Drop in the Mail App on Mac OS X Yosemite: Who set up his Macs iCloud has used, finds the appropriate Mail Account under the name "iCloud" is already in the Mail App. You can get a Mail Account quite quickly afterwards. As you can read here.
Mail Drop is for the iCloud E-Mail Account in Mail has been set up. If you want to but Mail Drop for large attachments also for another E-Mail account such as Gmail, GMX, or other services, then that works too. To do this you go into the settings under "Accounts" on the "Advanced" tab, select the configured E-Mail account and set a check mark in "Large attachments with Mail Drop-send". So that land attachments will be encrypted in iCloud.
If you this way a E-Mail from the Mail App with a large attachment to send, the recipient receives your E-Mail with an accompanying text. The recipient of the Mail can then click on the inserted Download button, whereupon its Mail Client the attachment from iCloud downloads. Uses the Mail recipients to other mail servers, this also works.
The Mail Drop feature, the Mail App with the introduction of Mac OS X Yosemite, as an additional function, I find quite handy. If you see with Mail Drop, large files, such as image collections, sends, fills it with his Mail Account is not to be. Nevertheless, I would recommend it, large files before Sending by E-Mail whenever possible in advance of the file size a little to reduce. Imagine you have a folder with large images, it is always recommended, that it had to shrink a little.
You can free download MailDrop and safe install the latest trial or new full version for Windows 10 (x32, 64 bit) from the official site.