Connect As Sysdba On Windows Fails With ORA-12560: TNS:protocol adapter error (Doc ID 989716.1)

Last updated on DECEMBER 06, 2016

Applies to:

Oracle Database - Enterprise Edition - Version 10.2.0.1 to 12.1.0.2 [Release 10.2 to 12.1]
Information in this document applies to any platform.
***Checked for relevance on 07-Oct-2011***
*** Checked for relevance on 05-Apr-2016 ***


Symptoms

A 'connect / as sysdba' on Windows fails witb an ORA-12560 as shown:

C:\> sqlplus /nolog
SQL> connect / as sysdba
ERROR:
ORA-12560: TNS:protocol adapter error

Cause

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