Outlook The Operation Failed Error When Sending Email: How to Fix

You see an Outlook The Operation Failed error when trying to send an email. This error stops your message from being delivered and can appear with different error codes. The problem is usually caused by a corrupted email profile, incorrect account settings, or a conflict with an add-in. This article explains the root cause and provides steps to resolve the error and send your emails again.

Why the Operation Failed Error Occurs in Outlook

The Operation Failed error is a generic message from Outlook indicating it could not complete the send command. The technical root cause is often a breakdown in communication between Outlook and your email server or a corrupted local data file. A common trigger is an outdated or damaged Outlook Data File, which stores your emails, calendar, and contacts locally. When this file has errors, Outlook cannot process the send request correctly.

Another frequent cause is incorrect or changed settings for your mail server. If your password has expired, the server address is wrong, or your security protocol is outdated, the server will reject the send command. Third-party add-ins for features like CRM integration or antivirus scanning can also conflict with Outlook’s standard processes. They may try to scan the outgoing message and fail, causing the entire operation to halt.

Understanding the Error Codes

The error dialog sometimes includes a specific number, like 0x8004010F or 0x800CCC13. Code 0x8004010F often relates to a corrupted send/receive profile or a missing Outlook data file. Code 0x800CCC13 typically points to a server authentication failure, meaning your login credentials are not being accepted. While the steps to fix the error are similar, knowing the code can help confirm which solution is most likely to work.

Steps to Resolve the Operation Failed Error

Follow these steps in order. Start with the quickest fixes related to your account and profile before moving to more involved solutions.

1. Repair Your Email Account
   Open Outlook and go to File > Account Settings > Account Settings. Select your email account and click Repair. Follow the on-screen prompts; Outlook will often test and update your server settings automatically. Restart Outlook and try sending a test email.
2. Disable Conflicting Add-ins
   Go to File > Options > Add-ins. At the bottom of the window, set the Manage dropdown to COM Add-ins and click Go. Uncheck all boxes in the list and click OK. Restart Outlook. If sending works now, re-enable add-ins one by one to find the culprit.
3. Create a New Outlook Profile
   Close Outlook. Open the Control Panel and search for Mail. Click Mail (32-bit) to open the Mail Setup dialog. Click Show Profiles. Select your current profile and click Remove. Confirm the deletion. Then, click Add to create a new profile, re-adding your email account. Set this new profile as the default and start Outlook.
4. Run the Outlook Inbox Repair Tool
   Close Outlook. Press the Windows key + R, type scanpst.exe, and press Enter. In the tool, click Browse to locate your Outlook Data File, usually in C:\Users\[YourName]\AppData\Local\Microsoft\Outlook. Select the file and click Start. If errors are found, click Repair. After repair, open Outlook and attempt to send.
5. Check Your Outgoing Server (SMTP) Settings
   Go to File > Account Settings > Account Settings. Double-click your email account. Verify the Outgoing mail server (SMTP) name and port number with your email provider, like smtp.office365.com for Microsoft 365. Ensure the My outgoing server (SMTP) requires authentication box is checked, usually set to Use same settings as my incoming mail server.

If the Operation Failed Error Persists

If the main steps do not work, the issue may be more specific. Try these targeted solutions for related failure patterns.

Error Appears Only with Large Attachments

Your email server may have a strict size limit for attachments. Check your provider’s limit, often 20-25 MB. Compress large files using a tool like Windows File Explorer’s Send to > Compressed (zipped) folder feature. Alternatively, upload the file to a cloud service like OneDrive and send a sharing link instead.

Error Occurs After a Windows or Office Update

A recent update may have changed a system file or introduced a bug. Open the Windows Start menu, type View update history, and select it. Look for recent updates for Windows or Microsoft Office. You can try uninstalling a specific update by going to Settings > Windows Update > Update history > Uninstall updates. For Office updates, run a repair via Control Panel > Programs > Programs and Features, select Microsoft 365, and click Change > Quick Repair.

Outlook is in Offline Mode

Outlook cannot send emails if it is set to work offline. Check the status bar at the bottom of the Outlook window. If it says Working Offline, go to the Send / Receive tab and click the Work Offline button to toggle it off. The status bar should now show Connected.

Manual Configuration vs. Automatic Repair

Item	Automatic Account Repair	Manual Profile Recreation
Best For	Minor configuration drift or password changes	Severe profile corruption or persistent errors
Process Complexity	Simple, guided wizard	Manual, requires reconfiguring settings
Data Risk	None, data remains intact	Low, emails are stored on the server
Time Required	2-3 minutes	10-15 minutes
Outcome	Quick reset of server settings	Clean slate with a new local profile

You can now diagnose and fix the Outlook Operation Failed error. Start with the account repair tool for a quick resolution. If the error returns, creating a new mail profile is the most reliable long-term fix. For advanced users, checking the Application log in Windows Event Viewer can provide specific error details from Outlook to guide troubleshooting.