If your Snow License Manager (SLM) is displaying "There are 0 inventoried computers" :
First, check if the Location for the Inventory server is correctly configured in SLM.

Run these queries and check the results show correct configuration:

select * from SnowInventory.inv.ServerAddress
select * from SnowInventory.inv.ApiKey
select * from SnowLicenseManager.dbo.tblInventoryDatabase
select * from SnowLicenseManager.dbo.tblServerAddress
select * from SnowLicenseManager.dbo.tblAPIKey

Check if the IsAccessible column is set to a value of 1.

If not, go into the SMACC tool and change the Inventory source to switch on "Enable data updates":

Then perform the Data Update Job (DUJ) again.