Message type: E = Error
Message class:  FI - TR-FM Funds Management 
Message number: 843
Message text: Select at least one document type
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 FI843 ("Select at least one document type") typically occurs in the context of financial document processing, such as when you are trying to execute a report or transaction that requires you to specify at least one document type but none has been selected.
Cause:
No Document Type Selected: The most common cause of this error is that the user has not selected any document type in the selection screen of the transaction or report.
Configuration Issues: There may be issues with the configuration of document types in the system, which could lead to them not being available for selection.
User Authorization: The user may not have the necessary authorizations to view or select certain document types.
Solution:
Select Document Type: 
Go back to the selection screen of the transaction or report where the error occurred.
Ensure that at least one document type is selected. This is usually done by checking the appropriate checkbox Get instant SAP help. Sign up for our Free Essentials Plan.
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