How To Fix 1M028 - For period unit week only key date values 1-7 (Mo.-Su.) allowed

1M028 - Overview

• Message type: E = Error

• Message class: 1M - BKK: Abschluß

• Message number: 028

• Message text: For period unit week only key date values 1-7 (Mo.-Su.) allowed

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message 1M028 - For period unit week only key date values 1-7 (Mo.-Su.) allowed ?

  The SAP error message 1M028 indicates that when working with period units defined as "week," only key date values corresponding to the days of the week (1 for Monday through 7 for Sunday) are allowed. This error typically arises in scenarios involving planning, reporting, or data entry where a week-based period unit is expected.
  
  Cause:
  The error occurs when:
  
  A user attempts to enter a key date that is not within the valid range for a week (i.e., any value other than 1-7).
  The system is expecting a specific day of the week but receives an invalid input.
  
  
  Solution:
  To resolve this error, you should:
  
  
  Check Input Values: Ensure that the key date you are entering corresponds to a valid day of the week. For example:
  
  1 = Monday
  2 = Tuesday
  3 = Wednesday
  4 = Thursday
  5 = Friday
  6 = Saturday
  7 = Sunday
  
  
  
  Adjust Data Entry: If you are entering a date or period that does not align with these values,