Message type: E = Error
Message class:  CUSTOMER_DOWNTIME - Customer initiated Downtime 
Message number: 005
Message text: Function can only be called during execution of a job
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The SAP error message CUSTOMER_DOWNTIME005 indicates that a specific function can only be executed during the execution of a job. This error typically arises in scenarios where a function module or method is being called outside of the context of a background job, which is often required for certain operations in SAP.
Cause: Context Misalignment: The function you are trying to call is designed to be executed in the context of a background job, but it is being called in a different context (e.g., directly in a dialog session). Job Scheduling: The function may be part of a scheduled job that has not been executed yet or has been executed in a different context. Incorrect Function Usage: The function may have specific requirements or preconditions that are not being met when it is called.
Solution: Run in Background: Ensure that the function is called within a background job. You can schedule a job using transaction SM36
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