Attachment Issues

How to Find and Reduce an Oversized Outlook Email

Maira Mehtab Sep 22, 2026 868 views

Question details

The user needs to locate and reduce the size of an oversized email that is stuck in the Outbox and causing send or receive errors.

Product: Microsoft Outlook
Device & OS: not provided
Scenario: Fixing a stuck outgoing email that failed to send due to excessively large attachments.
Observed behavior: An oversized email becomes stuck in the email client's Outbox, preventing other emails from processing and triggering a send/receive error.

Before you start

Verify the maximum attachment size limit set by your email service provider (typically 20MB to 25MB) and set Outlook to 'Work Offline' to stop it from continuously trying to send the stuck message.

Solution 1Recommended

Locate and Edit the Oversized Email in Classic Outlook

Best for users on the traditional Outlook desktop application to quickly clear the Outbox and fix send/receive errors.

In the classic Outlook desktop application, oversized messages that fail to send are automatically stored in the Outbox. Modifying or deleting the message directly from here will restore your email functionality.

Open the Outbox Folder

Navigate to the Folder pane on the left side of your Outlook interface and click on the 'Outbox' folder.

Open the Stuck Message

Double-click the oversized email to open it in a new window. If it won't open, ensure you have enabled 'Work Offline' from the Send/Receive tab.

Remove or Replace Attachments

Right-click the large attachment and select 'Remove'. Alternatively, upload the file to a cloud service like OneDrive and paste the sharing link into the email body.

Send the Email

Once the large attachments are removed, click the 'Send' button to process the email successfully.

Work Offline Tip: If you cannot delete or edit the message, navigate to the Send/Receive tab and click 'Work Offline'. Restart Outlook and try editing the message again.

Solution 2

Find and Fix Large Emails in New Outlook, Web, or Mobile clients

Use this method if you are using the New Outlook interface, Outlook on the web, or third-party email clients where the Outbox behaves differently.

Free Microsoft Office alternative

Reduce Document Sizes Before Emailing with WPS Office

Struggling with large Microsoft Office attachments? Switch to WPS Office, a lightweight and free alternative that offers seamless compatibility with Word, Excel, and PowerPoint files, alongside built-in tools to compress documents before you email them.

1. Download and Install WPS Office: Get the free WPS Office suite from the official website and install it on your device.
2. Open Your Large Documents: Launch WPS Office and open the oversized document, spreadsheet, or presentation you intend to email.
3. Compress the File: Use the built-in File Compressor or PDF Toolkit to significantly reduce the file size, making it small enough to bypass Outlook's attachment limits.

100% compatible with Microsoft Office formats (DOCX, XLSX, PPTX)Built-in file compression tools to easily reduce PDF and document sizesLightweight application that won't slow down your computerFree to use with a familiar, easy-to-navigate interface

microsoft office alternative - wps office

Frequently Asked Questions

What is the maximum email attachment size limit in Outlook?

The default attachment size limit in Outlook is typically 20 MB for Exchange accounts and 33 MB for other accounts (like Gmail or Yahoo integrated into Outlook). If your files exceed this limit, the email will fail to send.

Why are my emails constantly stuck in the Outbox?

Emails usually get stuck in the Outbox due to excessively large attachments, a lost internet connection, an authentication error with your mail server, or an add-in interfering with the sending process.

How can I send large files if they exceed the Outlook limit?

The best way to share large files is to upload them to a cloud storage service such as OneDrive, Google Drive, or Dropbox. Once uploaded, you can generate a shareable link and paste that link directly into your email body.

Does zipping or compressing a file help with email limits?

Yes. Compressing files into a ZIP folder or using built-in PDF compressors can significantly reduce the overall size of your attachments, often bringing them below the 20 MB threshold required for sending.

Outlook & Email Problems