Before we repair Notification Server, we first need to understand in which scenarios repairing will help. If you face any issues in Notification Server and it is not working as expected then the repair feature might help. If you face any issues with any of the solutions, and repairing the solutions does not help, then repair of Notification Server can help.
The best option is repair rather than reinstallation. When you repair all your basic config files are reconfigured. Again repair doesn't delete all the existing data, but the recommendations would be to backup existing database or any custom policies before attempting a repair. Again NS will stop services and entire requests from clients will not be processed during repair. It usually takes 30 minutes to repair if everything goes smoothly.
Go to C:\programfiles\Altiris\Setup Files\NS
Right click on Altiris_NS and say repair. It will repair NS as per above screenshot. It will stop NS services. With NS you need to repair all the msi that are mentioned below.
Right click in Resource Management and say repair as per above screenshot.
Right click on Altiris Diagnostics and say repair as per above screenshot. These are basically diagnostic tools that are present - i.e., log viewer, profiler.
Right click on AppWeaver and say repair.
Right click on AlertManager and say repair as per above screenshot.
Right click on HelpdeskProxy and say repair as per above screenshot.
Right click on Altiris KBProxy and say repair as per above screenshot.
Once above steps are completed successfully the NS is repaired. You can now reboot Notification Server.