Can I delete a message in a project or a version?

Personal messages are one of the few areas where if you made a mistake, you can undo it by deleting it- but only if you are the owner of the message! 

If you are the owner of the message, next to it, you will see a DELETE button. Messages left by other do not have this option. This is so that the system is fully transparent and compliant! 

This does not apply to system messages (audit trail). 

You can hide these from your view (click on "Hide audit trail"), or through a rule for all users, but it is not possible to delete them from the system.