IFS10 Business Planning error of planning entry

Just installed the Business Planning/BP module in our IFS10 Test environment, and got an error message while trying to create a planning entry/unit: “The Accounting Code part does not exist”.  Here is my questions:

1. Do I have to setup some special accounts for BP?
2. Is there a code part K? I am only aware of A~J
3. How to resolve this error.

best,

David