Accounts Payable Parameters Error: FormFunctionButtonControl object does not have method 'separator'

Hi,

Accounts payable parameters does not open and an error pops up instead. The error says:

"

Error executing code: FormFunctionButtonControl object does not have method 'separator'.

Stack trace

(C)\Classes\FormFunctionButtonControl\separator
(C)\Classes\LedgerDimensionDefaultAccountController\parmControl - line 11
(C)\Forms\VendParameters\Methods\init
(C)\Classes\SysSetupFormRun\init - line 3

"

How can I fix this.

Thanks