Hello All, This is just FYI post, As i found out that the solution to my problem was not documented any where. I tried both metalink and google. we were trying to clone our Windows - Oracle 11i Ebusiness Suite on 10gR2 Rac to a single node instance (Non-Rac). While trying to bring up the instance, it failed with ORA-29702: error occurred in Cluster Group Service operation I quickly figured out thats its looking for CRS and we dont have one on this box as its supposed to be a single node non-RAC instance. we raised a SR on metalink and they came up with following solution - Shutdown the instance which is cloned to non RAC. - Shutdown all the listeners. - Relink Oracle executable with rac_off option. $ make -f ins_rdbms.mk rac_off $ make -f ins_rdbms.mk ioracle - Remove all the parameters from init.ora which points to second instance and it is on other node. - Remove cluster_database parameter - Remove undo_tablespace parameter which points to second instance Sounds familiar right. Its the procedure to turning of RAC on Unix platforms not on windows. I updated the SR to clarify the procedure for windows, still there is no response there. After diving in with Sysinternal utilities (now its Microsoft) , finally found out the solution to my problem just rename following file in %ORACLE_HOME%/bin directory orarac10.dll to orarac10.dll.bak and it disabled RAC on windows. Actually we almost started installing a fresh 10gr2 oracle home, but found the fix just before that. As i don't maintain a blog, i guess this post here gets indexed by google and helps people trying to do this activity in future Thanks Vasu Balla