I have a workflow that schedules appointments to two different Outlook calendars based off of user selection for a Forms process. Last Friday around 7:30 Pacific, the Workflow started throwing the "Object reference not set to an instance of an object" error out of nowhere and is now unable to schedule anything.

There were zero updates to anything related to this and it had been working earlier in the day. Workflow, web service, licensing, user accounts, no updates at all. I can manually set appointments on the aforementioned calendar even, but obviously I need Workflow to be able to do it for the users using this application.

Any ideas on what I can do to get this working again?