Determining the Logon Language
The logon language is defined in the application server ABAP in the following way:
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1. If the Mandatory Logon Data flag has been set for a service in Transaction SICF, the system uses the language that was entered there.
2. If this is not the case, but the HTTP request contains the language in the HTTP header (as a header or a form field), you log onto the system using this language.
3. The browser settings of the calling client are then used. The system selects as the logon language the first language from the list that is maintained in the browser, and which is also installed in the SAP system.
The language list is specified using the HTTP header field accept-language.
With Internet Explorer, you can for example set the language you require by choosing Tools → Internet Options → Languages.
4. If the logon data flag is set in transaction SICF for a service (and is not flagged as mandatory), the language entered there is used).
5. If no language is defined by this process, the classic SAP system mechanisms are used. The logon language is based on the user settings (in transaction SU01) and if nothing is entered here, the default language of the SAP system is used automatically.
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