Reference Guide
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RDP Proxy
RDP Session Count Limit Settings
the number of simultaneous sessions of users using rdp proxy can be limited in this way, the number of concurrent sessions of a user group can be controlled to set a time limit navigate to users click the desired user group options, then click the edit button click the custom properties button section add the simultaneoussessionlimitrdpproxy property with the value of session limit count save property and save user group when sesison lmit exceed, the warning message is appeared on rdp proxy connection screen rdp simultaneous session exceeded message