Message type: E = Error
Message class:  FINS_FI_MASS_DATA - Mass Data Handling 
Message number: 135
Message text: Upgrade still running. Function is currently not available
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.
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The SAP error message FINS_FI_MASS_DATA135 with the description "Upgrade still running. Function is currently not available" typically indicates that a system upgrade or a background job related to the upgrade process is still in progress. This can prevent certain functions or transactions from being executed until the upgrade is completed.
Cause: Ongoing Upgrade Process: The most common cause of this error is that the system is in the middle of an upgrade process, and certain functionalities are temporarily disabled until the upgrade is fully completed. Background Jobs: There may be background jobs related to the upgrade that are still running, which can lock certain functionalities. System Lock: The system may be in a locked state due to the upgrade, preventing access to specific functions.
Solution: Wait for Completion: The simplest solution is to wait until the upgrade process is fully completed. You can check the status of the upgrade in the SAP system logs or by
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