If when using the Rebate Processing function you receive the error: 'Problem with selected nominal account X cancelling postings to protected account XXX'
Where X is the amount of postings cancelled and XXX is the nominal account that the process is trying to post to. As the error states, the Nominal Account targeted is marked as a Protected Account which means the process cannot post to it.
To resolve this error, set the nominal account to Protected No and you will be able to complete the Rebate Process:
Click Nominal Ledger (Accounts) then click Nominal Accounts.
Scroll or search for the Nominal Account in question.
Select the Attributes tab.
Set the Protected option to No.