Un-qualifying helps you to hide/move the unwanted profiles from the candidate pool. When a candidate is unqualified, the resume will be moved to a separate group and you cannot carry out further activities like associating to a job opening, scheduling interviews etc.,

To un-qualify a candidate:

1. Go to Candidates tab.
2. In the List view, enable the check-boxes of the candidates who needs to be unqualified
3. Click on Un-qualify link from Select options menu.
   The status of the selected candidates will be marked as Un-qualify.

Note: You will not be able to locate the un-qualified candidate's profile via search results. It can be reverted only through the Filter options.