OPTION 1:For ArcView Concurrent Licensing save the following as viewer.reg. and run as a script, batch file, or software push. (Change @YOUR_LICENSE_SERVER_HOSTNAME to your license server host value)Windows Registry Editor Version 5.00[HKEY_LOCAL_MACHINE\SOFTWARE\ESRI\License10.0]"SEAT_PREFERENCE"="Float""SOFTWARE_CLASS"="Viewer""LICENSE_SERVER"="@YOUR_LICENSE_SERVER_HOSTNAME"For ArcEditor Concurrent Licensing save the following as viewer.reg. and run as a script, batch file, or software push. (Change @YOUR_LICENSE_SERVER_HOSTNAME to your license server host value)Windows Registry Editor Version 5.00[HKEY_LOCAL_MACHINE\SOFTWARE\ESRI\License10.0]"SEAT_PREFERENCE"="Float""SOFTWARE_CLASS"="Editor""LICENSE_SERVER"="@YOUR_LICENSE_SERVER_HOSTNAME"For ArcInfo Concurrent Licensing save the following as viewer.reg. and run as a script, batch file, or software push. (Change @YOUR_LICENSE_SERVER_HOSTNAME to your license server host value)Windows Registry Editor Version 5.00[HKEY_LOCAL_MACHINE\SOFTWARE\ESRI\License10.0]"SEAT_PREFERENCE"="Float""SOFTWARE_CLASS"="Professional""LICENSE_SERVER"="@YOUR_LICENSE_SERVER_HOSTNAME"OPTION 2:Set the ESRI_SOFTWARE_CLASS environment variable as follows:For ArcView licensing:ESRI_SOFTWARE_CLASS = ViewerFor ArcEditor licensing:ESRI_SOFTWARE_CLASS = EditorFor ArcInfo Licensing:ESRI_SOFTWARE_CLASS = Professional