Riverside County apologizes for ‘unacceptable’ vaccine appointment website meltdown Just hours after thousands of residents experienced massive technical issues while trying to sign up for a vaccine clinic, Riverside County has announced it will change its website. Download the News Channel 3 app on the Apple Store or Google Play to get alerts on when new appointments or vaccine clinics are available. The county made 3,900 appointments available Thursday at noon. However when residents went to sign-up, many were met with a blank white "504 error" code page. Others who were able to get into the website filled out pages of registration forms only to find that the appointments had been filled.