Message type: E = Error
Message class:  STRALAN_MSAG - Language Transport Messages 
Message number: 028
Message text: Choose a supplementation language first
Before you can supplement a language, you must assign it a valid
supplementation language.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Use Transaction SMLT to assign a supplementation language.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message STRALAN_MSAG028, which states "Choose a supplementation language first," typically occurs in the context of SAP applications that involve language settings, particularly in the area of master data or when dealing with multilingual content.
Cause: This error usually arises when the system expects a user to select a "supplementation language" but none has been chosen. The supplementation language is often used in scenarios where multiple languages are supported, and the system needs to know which language to use for additional information or translations.
Solution: To resolve this error, you can follow these steps: Select a Supplementation Language: Navigate to the relevant screen where the error occurs. Look for a dropdown or selection field labeled "Supplementation Language" or similar. Choose the appropriate language from the list provided. Check User Settings: Ensure that your user profile has the correct language settings configured. You can check this in the user settings or profile options. Review Language Configuration: If you are an administrator,
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