Message type: E = Error
Message class:  CN_LDST_MSG - Message Class for Language-Dep. Short Texts Function 
Message number: 017
Message text: All languages are maintained; you cannot insert a line
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The SAP error message CN_LDST_MSG017 indicates that all languages are maintained for a particular entry, and therefore, you cannot insert a new line. This typically occurs in the context of maintaining texts for various languages in SAP, such as when you are trying to add a new text line for a material, vendor, or other master data that already has entries for all the required languages.
Cause: All Language Entries Exist: The system has already maintained text entries for all the languages defined in the system for the specific object you are trying to modify. Text Maintenance Settings: The configuration settings for text maintenance may restrict the addition of new lines if all language entries are already filled.
Solution: Review Existing Entries: Check the existing text entries for the object in question. If all language entries are indeed filled, you will need to modify or delete an existing entry if you want to add a
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