Problem: I try to upload an Image with a CRED form thru the front end as a guest. It fails with "There was an error uploading your file." I use the Toolset Access Plugin too.
Solution: If you use "Managed by Access" for Media, you can give the Guest only reading rights. Then it will fail to upload a media attachment.
If you use "Use the default WordPress read permissions" on the media post type, you can upload the images just fine as a Guest.
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