HTTP Strict Transport Security (HSTS) forces browsers to make secure HTTPS connections with websites.
However, when changing IIS Bindings, and especially after installing the certificate required to use BOX as a migration source, you may be denied access to the CloudM Migrate web UI with the error "You cannot visit cloudmigrator.local right now because the website uses HSTS"
Cloudmigrator.local needs to be removed from the HSTS list.
In Chrome, browse to chrome://net-internals/#hsts
Reload https://cloudmigrator.local - You may still get a certificate error but you should now be able to bypass this.