For our audits, we run VMware Health Analyzer (VMHA) on any vCenters to collect information on ESXi build numbers, snapshots, dormant VMs, etc. Recently, a customer we were scanning had two vCenters, and while VMHA worked fine on one of them, we were getting errors on the other. Standard troubleshooting didn't work, and the customer didn't know why we weren't able to collect the information this year. After running nmap on the vCenter, we determined the customer had redefined the port used for this vCenter instance and simply defining the port in our scan credentials solved the issue.