Message type: E = Error
Message class:  FOPCD - Message Class for Package FOPC_DOCUMENTS 
Message number: 104
Message text: Document '&1 - &2' already marked for deletion
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The SAP error message FOPCD104 indicates that a document (identified by the placeholders '&1' and '&2') is already marked for deletion in the system. This error typically occurs when you attempt to perform an operation on a document that has already been flagged for deletion, which prevents further processing.
Cause: Document Already Marked for Deletion: The primary cause of this error is that the document you are trying to process has already been marked for deletion in the system. This could happen due to a previous operation or a manual action taken by a user. Data Integrity Issues: Sometimes, inconsistencies in the data or improper handling of documents can lead to this situation. User Error: A user may have inadvertently marked the document for deletion without realizing it.
Solution: Check Document Status: Verify the status of the document in question. You can do this by using transaction codes like FB03 (Display Document) or other relevant transactions
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