This issue is typically present if the user account running the SFB scan doesn’t have the privileges to access the SFB server. The user account running the scan should be a part of the CsAdministrator, or CsViewOnlyAdministrator security group.
Another cause for the given issue can be if the OC Scanner tries to scan a Windows server which only houses SFB Management tools, or tries to scan an SFB server that doesn’t house any SFB users – such as SFB Edge Server/Mediation only server etc. depending on the SFB Topology. In order to correct this false positive scan alert, we would navigate to OC Configurator > Scan files > Specific scan file > Servers > Specific entry > User settings > Skype for business > Click on the Add button > Enter the FQDN or IP of the SFB server (depending on if the scan is defined through FQDN or IP), and toggle the SFB user scan to off. Save the changes, run the scan again, and the given alert should disappear.