UCM error :-The requested URL /idc/idcplg was not found on this server.

The error
The requested URL /idc/idcplg was not found on this server.
When I first installed ucm this error happened to come and I solved it .
Today While I try to install it for the secound instance it again showed .

Cause of this error is from apache configuration , U need to give the parameters propelry
My working ucm apache configuration contains entry as follows
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LoadModule IdcApacheAuth "/oracle/ucm/server/shared/os/linux/lib/IdcApache2Auth.so"

IdcUserDB "idc" "/oracle/ucm/server/data/users/userdb.txt"
Alias /idc "/oracle/ucm/server/weblayout/"

IdcSecurity idc
Allow from all
DirectoryIndex portal.htm


IdcUserDB "ge" "/ge-ucm/ge/server/data/users/userdb.txt"
Alias /ge "/ge-ucm/ge/server/weblayout/"

IdcSecurity ge
Allow from all
DirectoryIndex portal.htm