Core client application connectivity and availability across multiple platforms (Android, Windows). The issue points to a fundamental failure in establishing a secure connection to the backend service.

This issue highlights a critical service availability failure impacting both Android and Windows clients. The "tls handshake eof" error indicates a fundamental breakdown in establishing a secure connection to `huangguoai.com`. This is not a minor bug; it represents a complete inability for users to access the YellowFruit third-party client, rendering the product unusable. The absence of proxy configurations suggests a direct connection attempt failing at the TLS layer, potentially due to server-side misconfiguration, certificate issues, or network blocking. For a B2B SaaS offering, such a core connectivity failure is catastrophic, directly impacting user retention and trust. Immediate resolution is paramount, as prolonged downtime translates directly to lost business and reputational damage. This points to a lack of robust connection resilience or inadequate monitoring of core service endpoints.