We are aware of an issue earlier today where some users were unable to login to arlo.netgear.com starting around 10:30am PT. This appears to have been due to a nationwide outage with Comcast. Comcast is now reporting that service has been restored for most of their customers. If you are still experiencing an issue with logging into arlo.netgear.com, you can check the Comcast outage status in your area here.
Can you give us details about what you're experiencing? This will help us understand why you may still be experiencing an issue.
At what point are you seeing a problem (before or after you login)? Are you seeing an error messages?