Hi,
when a interface is in etherchannel we do not have any control protocol running between the links like LACP or Pagp.
start from basic
--first delete the interface configuration
--check for interface duplex and speed to auto and if it is fiber check for UDLD
--after deleting the configuration check for the ports are in default vlan
--check the interface is coming up without etherchannel and check for the UDLD settings
--then goto the interface mode
and
#sw mode access
#channel-group 1 mode on -- on both ends it should be ON mode.
then add the interface to this channel group.
--create an etherchnnel on both sides and check it out it is coming up
--any changes regarding the VLAN or IP address make changes only on the logical inteface
--still not working then enable LACP or Pagp on both end and check it out
--check for the cables also
still not working send me the configuration details and IOS information also.
Hope this helps,
Thanks,
GK