The attached file is missing. Please, attach the screenshots/video and elaborate more on this issue.
Were there any other settings changed in the Sitefinity project or only IP restrictions were set in IIS? Please, also restart the site and recycle the application pool.
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Sitefinity CMS Ideas&Feedback Portal
and vote to affect the priority of the items