When a Windows node is moved from SNMP to WMI monitoring, not all of the WMI Pollers are brought over. This report will show what nodes are missing pollers.
If any nodes are found, you can run this PowerShell script which calls into the SolarWinds API to add them programmatically.
https://thwack.solarwinds.com/content-exchange/the-solarwinds-platform/m/scripts/4351
