Denied User Reports Maintenance

How can I manage reports created by denied users?

This is a long string of if > thens, and the above question may not even be the correct question.

1. I need to remove some fields from my table, but they are used in many reports.
2. I've instructed users to update the fields on their reports, but, of course, people don't do what they're told.
3. If I go ahead and delete the field (or make it un-reportable), current users will receive an error saying that the report doesn't work. Either the field is being displayed or used in a filter or some other configuration option.
4. When I look at the fields' "usage", the fields are still being used on many reports (in some cases, over 700 reports). I found out that some of the reports are created by denied users, but some are still current users.
5. I cannot see the "Owner" of the report on the Field Usage screen (is this a separate issue?).

I think if I can at least remove the reports created by denied users, it will be easier to figure out whose reports are using the old fields and help them update their reports.
Does anyone have any other ideas on how to maintain reports?

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Anna Tamaoka
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