Best Open Source Windows Server Calendar Software 2026

Calendar Software for Windows Server

Calendar Windows Server Clear Filters

Browse free open source Calendar software and projects for Windows Server below. Use the toggles on the left to filter open source Calendar software by OS, license, language, programming language, and project status.

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1

Vtiger CRM

An enterprise-class CRM and more!

Vtiger CRM enables sales, support, and marketing teams to organize and collaborate to measurably improve customer experiences and business outcomes. Vtiger CRM also includes email, inventory, project management, and other tools, providing a complete the business management suite. Download Vtiger CRM here or sign up for a free 15-day free trial of the cloud-based application with free updates and support at https://www.vtiger.com/

91 Reviews

Downloads: 631 This Week

Last Update: 2025-07-09
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2

Google Calendar Client for Windows

Windows Client for Google Calendars

A small "Green" (and portable) Windows client that can retrieve events from multiple Google Calendars*, and display them on your PC.

Downloads: 0 This Week

Last Update: 2015-08-01
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3

Bumblebee Instrument Management System

Equipment/instrumentation booking and usage accounting system. Designed primarily for use in academic laboratories where a number of users share a set of instruments (e.g. NMR machines, microscopes, fume hoods).

Downloads: 0 This Week

Last Update: 2012-09-20
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4

KABE-Calendar

The "KABE-Calendar" is "free desktop calendar software" such as "wall hangings calendar". to display for up to one year.

Downloads: 0 This Week

Last Update: 2013-04-26
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5

OutlookWebCalendar

OutlookWebCalendar zeigt Frei/Gebucht-Informationen (die auf einem Exchange-Server gespeichert sind) von Gruppenmitgliedern übersichtlich in einer ASP-Anwendung an. Der Zugriff findet per "Exchange Web Services" statt.

Downloads: 0 This Week

Last Update: 2021-03-04
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6

Remote Calendars

RemoteCalendars is a COM-.NET Add-in for Outlook 2003/2007, written in C#. After installing this plugin, every Outlook user should be able to subscribe, reload and delete a generic remote iCalendar (RFC 2445) from Outlook 2003/2007.

10 Reviews

Downloads: 0 This Week

Last Update: 2013-05-01
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