Diagnosis
The G/L account has not been created in the company code in which youare working.

Procedure
INCLUDE MB_NA_SACHKONTO
If you have entered the G/L account or the company code yourself, checkthe account number entered, as well as the company code in which youare working.
G/L acct. CoCode
wrong right Correct the G/L account.
right wrong Correct the company code.
right right The G/L account must be created
for the company code.