Send large files in Outlook

What SendTheStuff will do when Outlook says it's too big

SendTheStuff will take the file Outlook refused and give you a link to paste into the message instead. Your email will carry a line of text, not the file, so none of Outlook's size checks will stop it.

SendTheStuff will keep the file at full quality, with nothing zipped or shrunk. The free plan will take up to 5 GB per transfer. That's far above Outlook's default attachment caps, and above the 2 GB Outlook.com allows for a OneDrive link.

How it will fit each version of Outlook:

• Classic Outlook for Windows. Instead of attaching the file and meeting the error box, you'll paste the link into the message body. The 20 MB default, or your mail server's limit, won't come into it.
• New Outlook and Outlook on the web. Outlook.com counts text and attachments together against its 25 MB cap. A pasted link adds one line of text to that count, never the file.
• Outlook for iOS and Android. Skip the paperclip icon. SendTheStuff will work in your phone's browser, so you'll copy the link there and paste it into a new message in the Outlook app.
• A work mailbox. Whatever cap your administrator set, a link stays under it. Your company's rules on outside services still apply.

Each SendTheStuff link will work for 14 days, then the file will be deleted for good. It won't sit in your OneDrive or swell your Sent folder.

"Bigger than the server allows": what Outlook is telling you

When you attach something too big in classic Outlook for Windows, it shows:

The file you're attaching is bigger than the server allows. Try putting the file in a shared location and sending a link instead.

Microsoft gives two different reasons for that error, depending on your account:

• An internet account (POP3 or IMAP). Classic Outlook itself refuses attachments that add up to more than 20 MB, whether that's one big file or several smaller ones. Microsoft says this default prevents your computer from continually trying to upload very large attachments that most providers would reject anyway.
• A work mailbox. The limit comes from the mail server's maximum send size, which your administrator sets. For Microsoft 365 work mailboxes, Microsoft's default is 35 MB for sending. On an older, on-premises Exchange Server, the default is 10 MB.

That exact wording is classic Outlook's. Whichever Outlook you use, the error itself points away from attachments: put the file somewhere shared and send a link.

Which Outlook you're using, and its limit

OneDrive: Microsoft's own workaround

Microsoft's advice for big files is to upload them to OneDrive, then "copy the link, and paste it into your email message". In Outlook.com, OneDrive links don't count toward the email size limit, and a linked file can be up to 2 GB.

That's a good choice if you already keep the file in OneDrive and want it to stay there. For a one-off send, it has catches:

• It uses your storage. The file counts against your OneDrive space until you delete it, and a few big videos fill that up quickly.
• It stops at 2 GB. Outlook.com won't send a bigger OneDrive file as a link. Anything larger needs a different service.
• Sharing settings trip people up. A link limited to specific people makes everyone else sign in or verify their email first.
• Nothing tidies up after you. Unless you or your IT team set an expiry, the link keeps working until you stop sharing the file or delete it.

SendTheStuff will skip those catches. Nothing will land in your OneDrive, and each SendTheStuff link will expire after 14 days.

Raising classic Outlook's limit, and why it rarely helps

Microsoft documents a registry value, MaximumAttachmentSize, that changes classic Outlook's 20 MB default for internet accounts. It only moves Outlook's own check. Your email provider's server still has its limit, and so does the recipient's. So a bigger attachment often just fails later, after you've waited for it to upload.

Microsoft also tells you to back up the registry before editing it. For most people, a link is quicker and safer.

Sending to people outside your organization

At work, attachments to outside addresses can run into the company's own rules as well as the size limit. Check your company's policy before sending work files through any outside service.

Many companies let you share a OneDrive file with outside people, but an administrator can switch that off. If a link won't open for someone outside the company, that's usually why, and only IT can change it.

SendTheStuff's free plan will be for personal, non-commercial use. So it will suit personal files from a personal Outlook.com address, not work files.

Until SendTheStuff launches

Microsoft's OneDrive route gets most files through Outlook in the meantime:

1. Put the file in OneDrive, or in whichever cloud storage you use.
2. Share it so that anyone with the link can open it, and copy the link.
3. In Outlook, start a new message and paste the link into the body where you'd have attached the file. This works the same in new Outlook, classic Outlook and Outlook on the web.
4. Send. The email is a few lines of text, so it's nowhere near any limit.
5. Once the recipient has the file, stop sharing it or delete it, so it stops using your OneDrive space.

On your phone: Outlook for iOS and Android attaches files with the paperclip icon on the New mail screen. For a big file, skip that: copy a share link from your storage app instead. Then paste it into a new message in the Outlook app.

When it doesn't work

• The error appears for a file under the limit you expected. Check the total of all attachments, not just the newest one, and remember that at work the limit is whatever your administrator set. Send a link either way.
• You raised the registry limit and the email still bounces. The server's limit, or the recipient's, is lower. Send a link.
• The recipient can't open your OneDrive link. Check the file's sharing settings in OneDrive. Switch it to "Anyone with the link" if your account allows it, then send the new link.
• Outlook attached a copy instead of a link. When you add a cloud file through the attach menu, Outlook can offer to attach it as a copy, which counts toward the limit. Paste the link into the body instead.
• The file is over 2 GB. That's past what Outlook.com will link from OneDrive. SendTheStuff will take up to 5 GB per transfer; until it launches, share the file from other cloud storage and paste that link.