Leads in a GoToWebinar event program have a "registration error" status.
This is caused by Marketo losing connection with the GoToWebinar service. To resolve this
- Go to Admin > Launchpoint.
- Open the GoToWebinar service.
- Re-enter your GoToWebinar credentials.
Once this is done, you can go back to the webinar program and change the status of the affected leads from "Registration Error" to "Registered."