27101, 00000, "shared memory realm does not exist"
// *Cause: Unable to locate shared memory realm
// *Action: Verify that the realm is accessible
You probably need to set your database service to start automatically. If it is started automatically, then you probably need to reconfigure the registry entries to set your SID to start automatically (since the service does not necessarily start an instance). If memory serves, you'll want to review the registry entries at HKLMSoftwareOracleHome0 and look for registry keys that have your ORACLE_SID name in them. One of them will be a Boolean (TRUE/FALSE) setting for whether or not to start the instance.
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