The button on the Deductions tab of a Creditor record will be greyed out if there are outstanding payments to be made to the creditor. Payments for creditors become outstanding once the End of Pay is processed and the fields will be greyed out until the Creditor EFT payment file has been created.
To create the Creditor EFT file:
Go to Payroll, Transactions, Import and Export, Creditor EFT Export.
Enter the parameters ensuring:
the Creditor is included
Payroll Company, Location and Pay Frequency are set to <All>
the Process To date is the last Period End Date
Tick Include Previous Year if you receive a message that there are outstanding payments for a previous year
Click Preview to reconcile the values first.
Click EFT File to produce the Creditor bank file. This will then need to be uploaded to your bank if you need to pay the creditor.
Go back to Payroll, Maintenance, General, Creditors and you should now be able to add the new deduction.
If, after completing the above steps, you still can't add a new deduction to a creditor, raise a case online. Include a description of the issue and reference this article.