TREX error Index does not exist;index=saf:cda_350_kaen in knowledge search

Hi,

Please help me any body i got below error in knowledge search in web ui

TREX error Index does not exist;index=saf:cda_350_kaen in knowledge search

i have been completed all Knowledge base settings in Name and Configure Knowledge Base

Application settings in Configure Application. but still iam getting above error.

Regards,

kanth