Outlook for Windows can’t attach a folder directly, but you can send everything in one attachment by zipping the folder first. In File Explorer, right-click the folder and select Compress to > ZIP file (in Windows 10, Send to > Compressed (zipped) folder). Then start a new email in Outlook, select Attach file, and choose the ZIP file. If the ZIP is larger than about 20 MB, upload the folder to OneDrive and send a link instead.
Applies to: new Outlook and classic Outlook for Windows, Outlook on the web, Outlook.com and Outlook for Mac. Last reviewed October 7, 2026.
Why Outlook won’t attach a folder
Email attachments are individual files. When you try to attach or drag a folder into an Outlook message on Windows, Outlook either does nothing or attaches only the files you select. A ZIP file solves this: it packs the whole folder, including subfolders, into a single compressed file that the recipient can open on any computer or phone.
Outlook for Mac is the exception. When you attach a folder there, it compresses the folder into a ZIP file for you, as described in Microsoft’s guide to attaching a file or folder in Outlook for Mac.
Step 1: Zip the folder
In Windows 11
- Open File Explorer and find the folder you want to send.
- Right-click the folder and select Compress to > ZIP file.
- A ZIP file with the same name appears next to the folder. Press Enter to keep the name, or type a new one.
In Windows 10
- Right-click the folder in File Explorer.
- Select Send to > Compressed (zipped) folder.
- Rename the new ZIP file if you want, then press Enter.
The original folder isn’t changed. If the files are sensitive, you can add a password to the ZIP with a free app; see how to password protect a ZIP file on Windows 11.
Step 2: Attach the ZIP file in Outlook
New Outlook and Outlook on the web
- Select New mail.
- On the Insert tab, or in the message toolbar, select Attach file (the paper clip).
- Select Browse this computer and choose the ZIP file.
- Add your recipients, subject and message, then select Send.
Classic Outlook
- Select New Email.
- On the Message tab, select Attach File > Browse This PC.
- Choose the ZIP file and select Insert.
- Finish your message and select Send.
You can also drag the ZIP file from File Explorer straight into an open message in any version of Outlook.
Shortcut from File Explorer (classic Outlook only)
If classic Outlook is your default email app, right-click the ZIP file and select Show more options > Send to > Mail recipient. Outlook opens a new message with the ZIP already attached. This shortcut doesn’t work with new Outlook.
If the folder is too big to email
Most email services limit attachments to about 20 to 25 MB, and the recipient’s limit can be lower than yours. For larger folders, share a link instead of attaching a file:
- Open File Explorer and select OneDrive in the left pane.
- Drag the folder into OneDrive and wait for the green check mark that shows it’s finished uploading.
- Right-click the folder and select Share.
- Enter the recipient’s email address, or select Copy link and paste it into an Outlook message.
- Choose whether people with the link can edit or only view, then send.
The recipient opens the whole folder in their browser and can download it as a ZIP. Nothing is attached, so size limits don’t apply. In new Outlook and Outlook.com, when you attach a file that’s too large, Outlook also offers to upload it to OneDrive and send a link for you.
Send the emails in an Outlook folder
If you want to send a folder of emails, not files, there’s no ZIP step. Open the Outlook folder, select the emails you want (press Ctrl + A to select them all), right-click, and choose Forward. When you forward several messages at once, Outlook attaches them to a single new message.
Tips for sending a zipped folder
- Tell the recipient what’s inside. Some people are wary of ZIP files from unknown senders, and some company filters quarantine them. A short note about the contents helps.
- Remove files you don’t need before zipping to keep the attachment small.
- Don’t expect big savings on photos and videos. They’re already compressed, so zipping makes them only slightly smaller. Use a OneDrive link for large photo folders.
- Check the folder structure. Subfolders are kept inside the ZIP, so the recipient sees the same layout you had.
Troubleshooting
The attachment is too large to send
Split the folder into two or more ZIP files, or use a OneDrive link. Outlook’s limit applies to the total of all attachments in one message.
The recipient says the ZIP was blocked
Some email systems block ZIP files, especially password-protected ones, because they can’t be scanned for viruses. Send a OneDrive link instead.
Compress to isn’t in the right-click menu
In Windows 11, check that you right-clicked a folder or file, not empty space. If you only see a short menu, select Show more options and choose Send to > Compressed (zipped) folder.
Send to Mail recipient does nothing
That shortcut needs classic Outlook set as the default email app. With new Outlook, attach the ZIP from inside a message instead.
The recipient can’t open the ZIP on a phone
iPhones open ZIP files in the Files app, and most Android phones open them in their file manager. If they still can’t open it, a OneDrive link lets them view the files in a browser.
Frequently asked questions
Can I attach a folder in Outlook without zipping it?
Not in Outlook for Windows or on the web. Outlook for Mac zips the folder for you automatically. On Windows, a ZIP file or a OneDrive link are the two options.
Does zipping a folder change the files?
No. The files inside the ZIP are exact copies. When the recipient extracts the ZIP, they get the same files and folders you had.
How do I extract a ZIP file I received in Outlook?
Save the attachment to your PC, right-click it in File Explorer, and select Extract All. Choose where to put the files, then select Extract.
What’s the attachment size limit in Outlook?
Outlook.com and most Microsoft 365 accounts allow about 20 MB per message by default, though work accounts can be set differently. Microsoft’s guide to attaching files in Outlook explains the OneDrive option for larger files.
Related: Where did my folder list go in Outlook.
Related: How to create a link for a Word document.
Related: how to delete a folder in Outlook.
Related: how to change the send and receive frequency in Outlook.
Matt Jacobs has been working as an IT consultant for small businesses since receiving his Master’s degree in 2003. While he still does some consulting work, his primary focus now is on creating technology support content for SupportYourTech.com.
His work can be found on many websites and focuses on topics such as Microsoft Office, Apple devices, Android devices, Photoshop, and more.