before installation: [root@emami freeswitch]# pwd /usr/local/src/freeswitch [root@emami freeswitch]# vim modules.conf #applications/mod_blacklist applications/mod_callcenter #applications/mod_cidlookup applications/mod_cluechoo applications/mod_commands after installation: freeswitch@internal> status UP 0 years, 0 days, 0 hours, 10 minutes, 25 seconds, 715 milliseconds, 274 microseconds FreeSWITCH (Version 1.5.3b git 9ed53db 2013-07-06 00:50:57Z) is ready 0 session(s) since startup 0 session(s) - 0 out of max 30 per sec 1000 session(s) max min idle cpu 0.00/94.00 Current Stack Size/Max 240K/8192K freeswitch@internal> module_exists mod_callcenter false freeswitch@internal> mod_callcenter reload -ERR mod_callcenter reload Command not found!