Step One : Install operating system language
To install the East Asian Language Files on the web front end servers via Control Panel > Regional and Language Options then click the Languages tab. In the Supplemental Language section, tick to Install files for East Asian Language.
Step Two : Install MOSS 2007 & Run SharePoint Configuration Wizard (Skip if you have installed MOSS 2007 previously)
Step Three : Download Your Specific SharePoint Server 2007 Language Pack, and burn it to disk or extract the files out

You must install the language packs in the correct order. The correct order is as follows:
1. Windows SharePoint Services 3.0 language pack
2. Windows SharePoint Services 3.0 SP1 or SP2 language pack
3. Office SharePoint Server 2007 language pack
4. Office SharePoint Server 2007 SP1 or SP2 language pack
Step Four : Install the language pack according to above order
Step Five : Run/Re-run SharePoint Configuration Wizard
Step Six : Create New Websites and Site Collections with Language selection option

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