From time to time you will come accross some very usful error messages in Issue Navigator Plus. We tried to make tham as few as possible. Our goal was to make those messages very clear so confusion can be avoided.
Sub-task error
It is not possible to change sub-tasks to another type of issue or to change any other type of issue to a sub-task. This is because this transition cannot be done by one spep only. You have to specify the parrent issue that the sub-task will belong. At the moment this convertion does not work in Issue Navigator Plus.
Permission error
In this case you have to (as we suggest) contact jour Jira administrator, because the absence of some permission settings prevent you from making any kind of modification in the mentioned column. The root of the problem might be that the field is not on the projects screen or possible is not a mandatory field. Or simply you are not allowed to work with that field.
Epic Name error
It is not possible to set an Epic Name to another type of issue (task, bug, reminder). That is commen sence. Simple as that.
Issue Navigator Plus not jet supporting a fild
Unfortunatly, not all fields are supported by Issue Navigator Plus jet. We do our best to expend the list of supported fields that you can edit in Issue Navigator Plus, but sometimes it is just not possible to make the field editable. For more information on the subject, please see the Supported Fields page for a complete list of the fields taht Issue Navigator Plus supports at the moment.