Why is it so hard to send large files by email?

Sending files by email is very common today. But as you have probably noticed, transferring large files that way remains difficult, despite recent progress in data sharing. Why is that? And how can you get around it while keeping data secure in transit? We answer all of those questions below.

What limits do email providers impose?

Email providers expressly block attachments beyond a certain size. That threshold varies from one provider to the next.

The most popular email platforms in business use are Gmail, Outlook, Yahoo and ProtonMail. For messages going through Gmail and Yahoo, the limit is 25 MB. The combined size of files that can be sent from a standard Outlook account is 25 MB. With an Exchange account, which is what professionals are advised to use, an attachment cannot exceed 10 MB by default. And on ProtonMail, the maximum size of files you can attach to an email is 20 MB.

Why these limits?

Email providers do not block large messages without reason. Here are the main causes behind the limits these platforms impose:

• Large attachments overload the servers dedicated to email;
• Transferring large emails costs email providers more.

Heavy files overload mail servers

An email does not travel in a straight line. Before reaching its recipients, it passes through servers following a precise network protocol. As well as delivering messages, those servers handle several other mechanisms, authentication (of sender and recipient) and spam avoidance among them.

In that context, the larger a message is, the heavier the workload it creates on the servers. On a global scale, that means processing a great many heavy emails at once. Left unchecked, the result would inevitably be a failure to manage messages coming from a multitude of mailboxes. Hence the limits email providers apply as a matter of course.

Sending large emails costs providers more

The sending services email platforms offer require certain equipment to be in place. On top of that, sending any email at all generates overheads. Some of those costs are tied to encoding attachments: for a file to be sent by email, it first has to be converted into text and then decoded back into its original form in the recipient's inbox. That has a cost, which varies with the size of the attachment concerned. An email carrying a large file also:

• Takes longer to transfer;
• Uses more bandwidth;
• Increases the size and duration of backups (and of synchronisation).

All of that adds to the cost of running an email service. To avoid going under, email providers therefore prefer to handle as few heavy files as possible.

Options for sending large files in a company

Managing and sharing large amounts of data is routine in a professional setting. As a result, a cap on message size does a company no favours and can have a negative effect on productivity. In that context, having a professional way to transfer heavy files securely is vital.

NetExplorer, for sharing your large files

Cloud computing is currently the option best suited to companies' file sharing needs. It gives you considerable storage space and a set of dedicated sharing tools. NetExplorer was designed exclusively to meet the requirements of professional users. You get a complete collaborative platform optimised for sharing large files securely, with no size limit.

In seconds, you can exchange data with colleagues, suppliers or partners. The platform offers several features worth having:

• Setting access rights per shared folder (very practical for teams working together on projects);
• Automatic notifications and email alerts as soon as a file arrives;
• Event logs;
• A download link created for each shared file.

There is also a NetExplorer plugin for professionals using Microsoft's email client. It integrates directly into the Outlook interface and lets you send heavy files without constraint.

In short, NetExplorer guarantees quick management and sharing of your large documents, internally and externally, with a very high level of security.

Large file transfer websites

Websites specialising in transferring heavy files are practical too. They are generally free up to a certain threshold (around 2 GB for most). Among the better known are Firefox Send and WeTransfer. Many people use these sites to send files larger than 25 MB by email. They work very simply: the sender adds the file they want to send and enters their own email address along with the recipient's.

A link is then emailed to the recipient, who can collect the file by downloading it from the platform. Be careful, though: while you can transfer all sorts of files with these sites, they are not really built for professional use. The storage they offer is generally temporary, for instance, which is not much help to companies that need traceability. Some platforms also offer no real guarantee when it comes to data security.

Conclusion

Email providers set a size limit on attachments to avoid overloading their servers. It also lets them control the costs of running a mail service and make the best use of their storage. To get around the restriction, you can use a large file transfer solution built specifically for companies, such as NetExplorer.