Message type: E = Error
Message class:  RMSL - Labeling Application Messages 
Message number: 018
Message text: Enter the key date
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The SAP error message RMSL018, which states "Enter the key date," typically occurs in the context of the SAP Real Estate Management (RE) module. This error indicates that a key date, which is necessary for processing certain transactions or reports, has not been provided.
Cause: The error arises when a user attempts to execute a function or transaction that requires a key date to be specified, but the key date field is left blank. The key date is essential for determining the validity of data, such as rental agreements, valuations, or other time-sensitive information.
Solution: To resolve the RMSL018 error, follow these steps: Identify the Transaction: Determine which transaction or report you are trying to execute when the error occurs. Locate the Key Date Field: In the transaction screen, look for the field labeled "Key Date" or similar. This field is usually required for the transaction to proceed. Enter a Valid Key Date: Input a valid date
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