Caution: No plan line items are written when copying

What causes this issue?

For technical reasons, no lone items are written when plan data is
copied, even though the <LS>Write Line Items</> indicator is activated
in Customizing in the fiscal year-dependent version parameters for the
relevant combination of ledger, version, company code, and fiscal year.
In some circumstances, this can mean that, after plan data has been
copied, the totals records no longer match the line items.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Check whether you really want to perform this function or whether you
can cancel it.
If inconsistencies have already arisen between totals records and line
items as a result of line items not having been updated when plan data
was copied, you can delete such inconsistencies as follows:
By (temporarily) deleting the relevant combination (ledger, version,
company code, and fiscal year) from the <LS>Fiscal Year-Dependent
Version Parameters</> view.
By re-including the same entry in the fiscal year-dependent version
parameters (consequently, the <LS>Write Line Items</> indicator is
deselected).
By using transaction GLDE (new General Ledger Accounting) or transaction
GCDE (Special Purpose Ledger) to delete the plan line items (and not the
totals records!).
By activating the line items for planning the MIT update of the opening
balance.
As a result, the totals match the line items.
<ZH>General Information on Using the </><LS><ZH>Copy Model Plan</></>
<ZH> Function</>
The <LS>Copy Model Plan</> function is usually performed once per fiscal
year at the start of the planning process and is used to produce an
initial plan data basis (for example, using the plan data from the prior
year).
This plan data basis can now be used with the actual planning
transactions to enter the final plan data.
Consequently, it is not useful to copy plan data if (manually) planned
data already exists.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.