encounter encan licenses

zhaon1129

**ERROR: (SOCLIC-90): This command does not have the necessary license to run, you must get access to one of the following licenses before you can run the command:  encan.
Use 'setLicenseCheck -status' to see the current licenses in use and for more information.
encounter 1> setLicenseCheck -status
Current checked out base license : vdi (Virtuoso_Digital_Implem 8.1).
When checking-out an optional license, wait for up to : 0 minutes.
The base license allows the following optional licenses : enclp encms epsxl epsl etsxl
The automatic optional license check-out is limited by -optionList to : enclp encms encan epsxl epsl etsxl etsl cndc encng
Current checked out optional licenses : none
Please help.Why?what?How?