Windows App Portable - Protonmail

When locked, private keys are wiped from memory (decrypted state removed), but the encrypted SQLite cache remains. Requires re-entering mailbox password (or Windows Hello if enabled).

The Proton Mail Windows app offers in several dimensions: no browser extensions, support for Windows Hello, and integration with CredUI for anti-keylogging. It maintains full end-to-end encryption while adding encrypted local caching for offline access. However, its Electron foundation introduces memory overhead and a larger attack surface (Node.js integration) compared to a hypothetical native WinUI app. protonmail windows app

Comparison: The web app via ServiceWorker can also work offline but with stricter storage limits (browser quotas ~50-100MB vs desktop unlimited by OS). When locked, private keys are wiped from memory

So, is there a ProtonMail app for Windows? The answer is Here is a breakdown of your options. So, is there a ProtonMail app for Windows

Critical to the desktop app is that all decryption must occur on the client device. Thus, the Windows app must manage private keys and decrypted plaintext temporarily.