Unable to Log In to Tuta macOS App - "Connection to Server Lost"

[emeritaacuity0u]

Summary:
I'm unable to log in to the Tuta macOS app. The app attempts to log in but fails after displaying "organizing calendar events" and returns the error: "The connection to the server was lost. Please try again." I can successfully log in using the same credentials on the iOS app and web app.

Steps to Reproduce:

1. Launch the Tuta macOS app (Version: 246.241008.0).
2. Enter valid credentials (same credentials work on iOS and web).
3. Attempt to log in.
4. The app reaches "organizing calendar events" and then fails, returning the error.

Expected Behavior:

After entering credentials, the app should log in and display the inbox.

Actual Behavior:

The app fails to log in and returns the following error: "The connection to the server was lost. Please try again." This occurs after the app displays the message: "organizing calendar events."

Environment:

• macOS Version: 15.0.1 (24A348)
• Tuta App Version: 246.241008.0
• Network: Wi-Fi
• DNS Setup: Custom DNS (AdGuard DNS Personal), but app.tuta.com is not being blocked (NOERROR response in logs).
• Firewall: macOS firewall enabled, but no blocking of the app in logs.

Error Messages:

• "The connection to the server was lost. Please try again."

Troubleshooting Steps Already Taken:

• Verified that login credentials are correct (successfully log in on iOS app and web app).
• Checked that DNS and firewall settings are not blocking the app (logs show no errors).
• Reinstalled the app, but the issue persists.
• Verified there are no permission issues on macOS and no errors in the Console logs.
• Confirmed that the issue only occurs on the macOS app, as I can log in without issue on iOS and the web.

Additional Context:

• The app gets stuck at "organizing calendar events" before failing.
• Network setup (AdGuard DNS, macOS firewall) has been confirmed not to be the issue through log analysis.