Hi Scott,
If you are still running into this issue creating a sandbox I recommend reaching out to our Care team so they can help you take a look at your app and what is causing you to run into sandbox creation issues. You can create a support case right here in community by clicking on Support where it appears on the global navigation at the top of the community page. You can also create a case in Quickbase by clicking the question mark (?) icon that appears in the upper right hand corner of the global nav and selecting Manage Support Cases. They can give you a second set of eyes and help you figure out what is going on since unfortunately that error isn't specific on what is getting in the way.
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Evan Martinez
Community Marketing Manager
Quickbase
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