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The Correct NLS_LANG in a Microsoft Windows Environment (Doc ID 179133.1)

Last updated on JUNE 13, 2023

Applies to:

Oracle Database - Enterprise Edition - Version and later
Oracle Database - Personal Edition - Version and later
Oracle Database - Standard Edition - Version and later
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Microsoft Windows (32-bit)
Microsoft Windows Itanium (64-bit)
Microsoft Windows x64 (64-bit)


 To give an overview on how to correctly define the NLS_LANG variable on Microsoft Windows platforms.


DBA's configuring Oracle RDBMS clients on any desktop/server Microsoft Windows desktop/server platform (=excluding Microsoft Windows Mobile/CE/tablet).


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In this Document
 1. Key Concepts/terminology:
 1.1 Microsoft Windows Code Pages:
 1.2 Fonts:
 2. How to setup my NLS_LANG:
 2.1 In the Registry:
 2.2 As a System or User Environment Variable, in System properties:
 2.3 As an Environment variable defined in the command prompt:
 3. The correct NLS_LANG for my Microsoft Microsoft Windows Code Page for an non-Unicode Microsoft Windows application:
 3.1 Determine your Windows ACP code page (used by sqlplusW.exe):
 3.2 Find the correspondent Oracle client character set:
 3.3 Set it in your Registry:
 4. The correct NLS_LANG for my Command Prompt OEM Code Page (used by sqlplus.exe) :
 4.1 The default Microsoft Windows configuration
 4.2 changing the Microsoft windows Command Prompt environment to use an ANSI characterset like 1252
 5. How to check the NLS_LANG:
 6. List of common NLS_LANG's used in the Microsoft Windows Registry:
 7. List of common NLS_LANG's used in the Microsoft Windows Command Prompt  :
 8. The correct NLS_LANG for an Unicode Microsoft Windows application:
 9. How Windows uses Fonts to display the different charactersets:
 10. Updating/changing the NLS_LANG in the registry to the correct value:

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