Privacy firm Proton suffered a massive worldwide outage today, taking down most services, with Proton Mail and Calendar users still unable to connect to their accounts.

The outage started at approximately 10:00 AM ET, with Proton users unable to connect to their accounts, including ProtonVPN, Proton Mail, Proton Calendar, Proton Drive, Proton Pass, and Proton Wallet, due to networking issues.

"Investigating - We are currently experiencing intermittent network issues affecting some of our users," reads the Proton status page.

"We are working to fully restore services as soon as possible. We apologize for the inconvenience." 

While most of the services have been restored, Proton says that Proton Mail and Proton Calendar continue to suffer outages.

When attempting to connect to ProtonMail, some users still experience error messages stating, "Something went wrong. We couldn't load this page. Please refresh the page or check your internet connection."

Update 1:09 PM ET: Proton has restored connectivity to Proton Mail at 12:37 PM EST and BleepingComputer can confirm that the service is restored.

Proton is now working on restoring connectivity to Proton Calendar.

Update 3:04 PM ET: Proton said all services were restored by 1:27 PM ET.

BleepingComputer contacted Proton to learn more about the outage and will update our story if we get a response.

This is a developing story