Kolab Now Alternatives for Windows

Yahoo! Mail is a long-standing web-based email service offering various plans for personal and business use. It provides essential email functionalities along with integrated features like chat and calendar.

Mailpile is a free and open-source webmail client designed with privacy and encryption as core principles. It offers a self-hostable solution for managing your email with built-in support for PGP encryption and other security features, providing an alternative to traditional webmail services.

Enigmail is a robust extension for Mozilla Thunderbird and SeaMonkey, providing comprehensive OpenPGP encryption and digital signing for your email communications. It integrates seamlessly into these email clients, offering a user-friendly way to protect your privacy and ensure the authenticity of your messages.

Kopano is a versatile open-source groupware suite offering email, calendaring, contacts, and online collaboration tools for businesses and organizations. It provides flexible deployment options, including on-premises and hosted solutions, with strong focus on data privacy and security.

Wimi is an all-in-one collaborative workspace for teams. It integrates project management, task management, file sharing and synchronization, team chat, video conferencing, and shared calendars into a single platform to streamline teamwork and boost productivity.

Microsoft SharePoint is a robust, browser-based platform for collaborative document management and content sharing within organizations, designed to enhance teamwork and streamline workflows through its integrated suite of tools.

Microsoft Exchange Server is a robust mail and calendaring server designed for businesses of all sizes, providing enterprise-grade email, calendaring, and contact management capabilities.