We always recommend that you publish a new job ad so you get a correct and fresh recruiting process. Instead, you can copy the job ad and create a brand new one!
If this is a role that you recruit often create a Job template instead of republishing.
If you choose to republish:
No email will be sent out to all your candidates that have Connected with your company, informing them about the open position
Employees will not receive an email to share in their network
The statistics from previous period will still be there
The candidates from the previous recruiting will still be in the process.
However if you want to republish the archived job, go to the editing view and scroll to the bottom of the page. There, click the arrow right next to the save button (1) and then Unarchived (2).