Message type: E = Error
Message class:  PPESTATUS - Messages: iPPE Status Management 
Message number: 001
Message text: Key field must be filled
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The SAP error message PPESTATUS001: Key field must be filled typically occurs in the context of SAP's Production Planning and Execution (PPE) module. This error indicates that a required key field in a transaction or data entry screen has not been filled out, which is preventing the process from proceeding.
Cause: Missing Key Field: The most common cause is that a mandatory field, which is essential for the transaction or process, has not been filled in. This could be a field like Material Number, Plant, or any other key identifier that is required for the operation you are trying to perform.
Configuration Issues: Sometimes, the configuration of the system may require certain fields to be filled that are not typically mandatory in other contexts. User Input Error: Users may overlook filling in required fields due to oversight or misunderstanding of the form.
Solution: Identify the Missing Field: Review the transaction or data entry screen to identify
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