Is IDMSA Apple a Scam or a Legitimate Website? Questions and Answers Answers: 5 Views: 1,436 Save Updated: Dec. 6, 2019 2019-12-06T01:27:33 Posted: Dec. 6, 2019 2019-12-06T01:21:42 Online Threat Alerts (OTA) I want to know if the URL or website address idmsa.apple.com is a fake or phishing website, or is it a legitimate Apple website? The URL idmsa.apple.com is legitimate, it is Apple's central sign-in page or portal. Remember, once the right part of the domain name, which is apple.com is legtimate, everything that follows on the left side (idmsa.apple.com) is also legitimate.