You can use the Batch Edit Applicant Status plugin to change a list of Applicants / Candidates, which can be found on the RDB store. Once installed:
Click Home and then click Tag File.
Remove all records from the Tag file to ensure you do not affect incorrect records.
Tag the Applicant Records you wish to change to a specific status. You can do this by performing an applicant search through Search , Applicants.
Go back to your Tag File and click Save to create a new saved tag file.
Open the Saved Tag File you just created.
Click Edit Applicant Status from the View section in the options on the left side of the screen.
Choose the status from the drop down menu and click Update.