Message type: E = Error
Message class:  BL - Application Log 
Message number: 600
Message text: No transport request was specified
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
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The SAP error message BL600: No transport request was specified typically occurs when you are trying to perform an action that requires a transport request, but none has been specified or created. This can happen in various scenarios, such as when you are trying to release changes in the SAP system or when you are working with customizing or development objects. Causes: No Transport Request Created: You may not have created a transport request for the changes you are trying to make. Transport Request Not Assigned: The changes you are trying to transport may not be assigned to any transport request. Incorrect Transaction: You might be using a transaction that requires a transport request, but you are in a context that does not support it. User Authorization: The user may not have the necessary authorizations to create or assign transport requests. Solutions: Create a Transport Request: If you haven't created a transport request, you can do so by
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