How can I delete(inactivate) a user from jira after he leaves the company and also how can I reassign the tasks which he worked on.

[Ollie Guan · Accepted solution]

This depends on whether you have the permission of the Assignee  

Issue Permissions	Explanation
Assign Issues	Permission to assign issues to users. (See also Assignable User permission below)

https://confluence.atlassian.com/display/JIRA051/__project+permissions

[Ollie Guan]

It's better to deactivate the user than deleting.https://confluence.atlassian.com/display/JIRA/Managing+Users#ManagingUsers-Deactivatingauser

[Shankar Reddy guduri]

Thanks Ollie. How about the tasks which he worked on. Can I unassign the tasks which are in progress.