Problem:

In JIRA Service Desk Cloud, while setting a mail handler to support@domain.com we get and error, this email address is already in use by another project. However, the mail address is not configured as a mail handler anywhere in any project.

Cause:

This issue occurs is the first part of the mail address of the handler matches that of a default cloud mail handler in another project. For example, in an instance Project A has a default cloud mail handler as support@xyz.atlassian.net and for Project B we try to configure a custom mail handler support@domain.com. Though support@domain.com does not exist in any project, we will get this error as the first part of mail handler address of both projects is "Support".

Resolution:

• Go to the Project A --> Project settings
• Email requests
• Edit the Cloud email address support@xyz.atlassian.net  to a test address (Temporarily)
• Once the value Support is free, Create the Custom mail address in the required project.
• Once done Update the Cloud Email address in the Project A to support@xyz.atlassian.net.