Outlook error “Cannot send this item” when replying to an email

Last Updated: October 6, 2021

ISSUE

When you reply to an email that has long links in the body, Outlook may display the following error:

This can happen if the 2085th character in a link is an escaped character. This issue can also occur with long URLs and when processed with SafeLinks.

STATUS: INVESTIGATING

The Outlook team is investigating the issue and will update this article when more information becomes available.

WORKAROUND:

To work around the issue, you can do one of the following:

• Change the email format from HTML to Rich text. Go here for more information and detailed steps:  Change the message format to HTML, Rich Text Format, or plain text - Outlook (microsoft.com) 

• Remove any long links in the body of the email before replying.

• Reply to the email using Outlook Web App (OWA)

• Switch Office to Semi Annual Channel where the bug is not introduced. To do this, follow the steps here: Change the Microsoft 365 Apps update channel for devices in your organization