启用工作流后，审批处理时报错。

启用工作流后，审批处理时报错。
Object reference not set to an instance of an object.

发生时间：10:31:44
错误来源： Kingdee.BOS.VerificationHelper
错误信息：Object reference not set to an instance of an object.
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调用堆栈：
at Kingdee.BOS.VerificationHelper.VerifyFormHelper`2.Verify(Context ctx, LinkedFormId form)
at Kingdee.BOS.VerificationHelper.DBRecordsVerifier.CheckRecords(Context ctx, LinkedFormId form, Func`3 getRecordsFunc)
at Kingdee.BOS.ServiceHelper.DataCenterService.DemoLicControl(Context ctx, LinkedFormId form, Func`3 getRecordsFunc)
at Kingdee.BOS.Web.DynamicForm.AbstractDynamicWebFormView.LicControl(IDynamicFormView mainView, DynamicFormShowParameter param)
at Kingdee.BOS.Web.DynamicForm.AbstractDynamicWebFormView.ShowForm(DynamicFormShowParameter param, Action`1 action)
at Kingdee.BOS.Workflow.PlugIns.AssignApprovalBaseEdit.AfterBindData(EventArgs e)
at Kingdee.BOS.Core.DynamicForm.PlugIn.DynamicFormViewPlugInProxy.FireAfterBindData(EventArgs e)
at Kingdee.BOS.Web.DynamicForm.DynamicWebFormView.LoadData()
at Kingdee.BOS.Web.DynamicForm.DynamicWebFormController.LoadData()
错误数据： System.Collections.ListDictionaryInternal