Scenario:

Sharing a page with multiple users always returns an "Error while sending" message:

While sharing a page with a single user is not an issue as it returns the expected result which is "Sent"

However, Confluence sends all of the notifications without any problems (there is no queued messages, all users get their notifications). Nevertheless, this is a problem because this error is misleading and when users see this error message, they think their shared pages won't get through so they try to send it out again and again and this became a spam.

Resolution

This issue has been fixed in version 1.26.1 of the Share Page plugin. This is compatible for Confluence 4.3 and above. You can update the plugin by going to Manage Add-ons in Confluence Admin. If the update is compatible with your version of Confluence, it will be displayed in Action Required.