InfoPath Dev

We have created a sharepoint list and its default form is customized in Infopath. All works well. However when users access forms to add a new record in sharepoint list, default Site menu is also displayed on the Left side of form. Using this users can go and view various lists and site contents. We want to avoid showing this default site menu on the left of the form when users create new entry in list. See attached pic where the menu which is not expected to be displayed in highlighted in Red.

So - in the site settings, enable quick launch has been deselected? It just shows up after they add a new record? And this only happens if the new record is added to a list where the default form has been customized in InfoPath?

Thank you, it works. Under Site settings -> Navigation Elements -> Quick Launch is de-selected and it works as expected. Whenever user launch form, it is displayed and it will be there even after form is closed. Is there a possibility to close the browser itself after CLOSE button on Infopath Form. My issue is after submitting form to add new record in list, users can see site contents it means they can access and modify list data. is there any way we can stop users to access Lists directly?