Ray's post is a way to do it, but the users would still see the documents in the Accesspoint and would try to open them.
Being you are using IIS, I would set up a redirect that would send them to another web page that would provide the information that the QlikView Site is offline. During that time.
Bill - Principal Technical Support Engineer at Qlik To help users find verified answers, please don't forget to use the "Accept as Solution" button on any posts that helped you resolve your problem or question.
In addition to Ray's & Bill's suggestion, you could created Windows Scheduled Task to start and stop the QlikView Server Service. Doing so would result in a "No Server" error being returned while the QVS services was stopped.
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