Did you consider manual creation from any of the Work Order apps (ie WOTRACK, QUICKREP and equivalent from any Industry solution). If so then you need to remove the INSERT from any and all Security Groups for the specific application.
I'm curious why you need to freeze Work Order generation. If you are trying to perform system updates then "Admin Mode" might be a simple way as no users would be able to login and any of the automated processes like Cron Tasks, Escalations, Automation Scripts don't run in Admin Mode.
Hope that helps,
Mike
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Michael Marsonet
MRM-EAM Consulting Inc.
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