How to Attach a File in Outlook (and What to Do When It's Too Big)
Attaching a file sounds simple, and usually it is. The trouble starts when the file is a 40 MB video and Outlook refuses to send it, or when you attach the wrong version of a document for the third time. Here's how to attach files quickly — and the better option when they're too big.
Quick reference
| What you want | How |
|---|---|
| Attach a file | Attach → Browse this computer (or drag it in) |
| Attach a recent file | Attach → pick from the recent list |
| Send a big file | Attach → Browse cloud locations → share as a link |
| Size limit | Usually around 20–25 MB per email |
1. Attach a file to an email
New Outlook and Outlook on the web:
1. Click New mail.
2. Click Attach (the paperclip) on the toolbar.
3. Choose Browse this computer, find the file and click Open.
2. Click Attach (the paperclip) on the toolbar.
3. Choose Browse this computer, find the file and click Open.
Classic Outlook:
1. Click New Email.
2. On the Message tab, click Attach File.
3. Pick a file from the Recent Items list, or click Browse This PC…
2. On the Message tab, click Attach File.
3. Pick a file from the Recent Items list, or click Browse This PC…
The attachment appears under the subject line (or at the bottom of the message in some views).
2. Faster ways to attach
• Drag and drop — drag a file from File Explorer or your desktop straight into the message window.
• Copy and paste — copy a file in File Explorer, click in the message body and press Ctrl + V.
• Recent files — the Attach menu lists files you've recently opened in Word, Excel and other Office apps. Chances are the one you want is there.
• From Explorer — right-click a file in File Explorer and choose Share → Mail (or Send to → Mail recipient on older versions) to open a new email with it already attached.
• Copy and paste — copy a file in File Explorer, click in the message body and press Ctrl + V.
• Recent files — the Attach menu lists files you've recently opened in Word, Excel and other Office apps. Chances are the one you want is there.
• From Explorer — right-click a file in File Explorer and choose Share → Mail (or Send to → Mail recipient on older versions) to open a new email with it already attached.
3. When the file is too big
Most email systems reject attachments over about 20–25 MB, and the recipient's limit might be lower than yours. Instead of attaching the file, share a link to it:
1. Click Attach → Browse cloud locations (new Outlook) or Attach File → Browse Web Locations → OneDrive (classic).
2. Pick the file from your OneDrive. If it's not there yet, upload it to OneDrive first.
3. Choose Share as a OneDrive link when Outlook asks.
2. Pick the file from your OneDrive. If it's not there yet, upload it to OneDrive first.
3. Choose Share as a OneDrive link when Outlook asks.
The recipient gets a link to the file rather than a copy. You can send a 2 GB video this way, and if you fix a typo later, they see the updated version.
Tip: when you attach a large file from your computer, new Outlook often offers to upload and share as a OneDrive link automatically. Say yes.
4. Attaching several files
Hold Ctrl while clicking files in the Browse window to pick more than one. If you're sending lots of files, consider putting them in a folder first, right-clicking the folder and choosing Compress to ZIP file, then attaching the single zip.
5. Remove an attachment
Click the arrow (or ⋯) on the attachment and choose Remove. Or click it and press Delete.
Troubleshooting
"The attachment size exceeds the allowable limit." Share it as a OneDrive link (section 3), or compress it. Photos straight from a phone are often 5–10 MB each — pasting them into Word and saving as a smaller PDF helps.
The recipient can't open the OneDrive link. Click the link's permissions and set it to Anyone with the link, or add the recipient's email address so they can sign in.
I attached the wrong file. Remove it, then use the Recent list to grab the right one. Check the file name before you click Send — Outlook shows it under the subject.
Wrapping up
For anything small, drag it in. For anything big, send a OneDrive link — it's faster, has no size limit worth worrying about, and the recipient always sees the latest version.
