If you have a larger network environment it can happen that the IGEL Universal Management Suite will not find all Thin Clients.
This can have to reasons:
1) The network is slow and the clients can not answer fast enough, in this case increase the Time Out Parameter in the IGEL Universal Management Suite Administrator Tool->Ports/Timeouts->Scan Parameter->Timeout(ms). We recommend to double the Timeout for every try, take over the configuration and scan again.
2) The traffic is blocked by a router or a firewall, in this case configure a static Scan-Reply Port. To do this open the IGEL Universal Management Suite Administrator and browse to Ports/Timeouts->Scan Parameter->Enable Scan-Reply Port and setup a port. Do not forget to take over the configuration in the UMS Administrator and make sure the port is open/enabled in your firewall/router setup in advance!