Pop up issue with end button assert condition violated

Hi All,

I have been facing an issue. When I click on END button twice getting assert condition violated error. If i click on end button more than once it gives. If i click on end button second time while processing of first its throwing this message. For first click system gives a popup with ok and cancel. But for second click ( that clicked in waiting state ) gives blank pop up. If i close this pop up i get assert condition. Is there any note to over come this. ?

experts can you suggest ?

Regards

Damodar