CSCea46385 - ETHCNTR-3-LOOP_BACK_DETECTED:

[itsupport@jetsynthesys.com]

received same error on cisco 1000 Switch

Switch Ports Model SW Version SW Image
------ ----- ----- ---------- ----------
* 1 56 C1000-48T-4X-L 15.2(7)E4 C1000-UNIVERSALK9-M

Oct 18 08:18:36.744: %PM-4-ERR_DISABLE: loopback error detected on Gi1/0/24, putting Gi1/0/24 in err-disable state

Please Let us know the s

[MHM Cisco World]

There  is l2 loop in your network 

[Leo Laohoo]

Faulty cable connected to port 24. 

Post the complete output to the command "sh interface Gi1/0/24 controll".