SAP SERVER Oracle Database 12560 error

Check registry.

Go to command prompt:
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1. Type "regedit". The registry editor will open.
2. To be on the safer side, do an export of the registry before making changes.
3. Navigate to:
HKEY_LOCAL_MACHINE\SOFTWARE\ORACLE\KEY_
4. Click on KEY_ on the left pane. On the right pane you will be able to see the list of string values.
5. Place the mouse pointer on the space and right click. Click on "New">>"String Value".
6. Type the name "ORACLE_SID" and hit enter. Now double-click on the parameter "ORACLE_SID". Enter the name of ORACLE_SID and click "OK".
7. Close the registry editor.
8. You will be able to connect to the database directly from the command prompt without explicitly setting the ORACLE_SID parameter.


Start TNSListener in Service Panel.