Message type: E = Error
Message number: 026
Message text: First-level check: Enter a valid posting key (item number &1)
The posting key is not correct.
The system cannot balance or split the document.
You can post documents only if their debits and credits together sum to
You cannot post documents that have more than 990 line items.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Error message extract from SAP system. Copyright SAP SE.