Ecc 6.0 error

hi all

can u plz help me in resolving this error

im using Ecc 6.0 . when im posting in f-02 im getting an error " mess. no. GLT2076 no item category is assigned".

The description of the error contains "the online document splitting is active in ur system . here each document is assigned to accounting transaction variant and each document row to item category. you determine for each business transaction variant which item u can or must be posted.

the following erroroccured for the document u entered

no item category could be determined for account XXXXX for chart of accounts XXXX "