Cannot drill to a debtor system from the debtor maintenance form

On the Customer Activities > Debtor Systems tab of debtor maintenance, double right clicking the System Name produces the following error:

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Error
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Error : ClassName 'JiwaFinancials.Jiwa.JiwaDBSysTemplateUI.MainForm' was not found in the Forms Collection loaded from the table SY_Forms.
Module : CreateForm
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OK
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