|  | To enable alerts for Web application we use below code 
 $SPwebapp=Get-SPWebApplication "http://SharePointSite.com"
 
 $SPwebapp.AlertsEnabled = $true
 
 $SPwebapp.Update()
 
 # To Disable alerts for a Web application
 
 $SPwebapp.AlertsEnabled = $false
 
 $SPwebapp.Update
 |  |  |