Question:

What is the best way to create a company-wide calendar with shared categories in Outlook?

I am a sysadmin for a company of 50 employees and I need to set up a calendar that can be used by everyone to track time off, company events, and holidays. I have tried using a shared mailbox, a public folder, and a Microsoft 365 Group, but none of them worked well for me. Here are the problems I encountered with each option:

• Shared mailbox: It became unstable and unreliable when more than 25 users accessed it, as per Microsoft’s recommendation.
• Public folder: It did not support shared categories, which was a requirement from the president and HR of the company.
• Microsoft 365 Group: It did not show up in the Outlook desktop app unless Cached Exchange Mode was enabled, which caused issues with large inboxes and required a registry edit to increase the PST file size limit.

Is

there any other solution that can meet my needs? I would appreciate any advice from the experts. Thank you.

Answer:

If you are a sysadmin for a company that needs a calendar to share among all employees, you might have encountered some challenges with the available options in Outlook. You might have tried using a shared mailbox, a public folder, or a Microsoft 365 Group, only to find out that they have limitations or drawbacks that prevent you from meeting your requirements. In this article, we will explore these options and their problems, and then suggest a possible alternative that can help you create a company-wide calendar with shared categories in Outlook.

Shared mailbox

A shared mailbox is a mailbox that multiple users can access to send and receive email messages and to share a common calendar. You can create a shared mailbox in the Exchange admin center or using PowerShell commands. A shared mailbox can be useful for scenarios such as a customer service team or a project team that needs to collaborate on a calendar.

However, a shared mailbox has a major limitation: it is not designed to handle a large number of users. According to Microsoft, a shared mailbox should not have more than 25 users accessing it at the same time, otherwise it can cause performance issues, synchronization errors, or data corruption. This means that a shared mailbox is not suitable for a company-wide calendar that needs to be accessed by 50 or more employees.

Public folder

A public folder is a folder that is stored in the Exchange server and that can be accessed by multiple users. You can create a public folder in the Exchange admin center or using PowerShell commands. A public folder can be used to store different types of items, such as email messages, contacts, tasks, or calendars. A public folder can be useful for scenarios such as a company newsletter or a departmental calendar.

However, a public folder has a major drawback: it does not support shared categories. Categories are labels that you can assign to items in Outlook to organize them by color, name, or priority. Categories can be useful for a company-wide calendar to distinguish between different types of events, such as time off, company events, or holidays. However, categories are stored in each user’s mailbox, not in the public folder. This means that each user can see only their own categories, not the categories of other users. This can cause confusion and inconsistency when viewing or editing the calendar.

Microsoft 365 Group

A Microsoft 365 Group is a group of users that can share resources such as email messages, files, chats, or calendars. You can create a Microsoft 365 Group in the Microsoft 365 admin center or using PowerShell commands. A Microsoft 365 Group can be useful for scenarios such as a team collaboration or a project management.

A Microsoft 365 Group has some advantages over a shared mailbox or a public folder. For example, a Microsoft 365 Group can support up to 5,000 members, which is much more than a shared mailbox. A Microsoft 365 Group can also support shared categories, which is not possible with a public folder. A Microsoft 365 Group can also integrate with other Microsoft 365 apps and services, such as Teams, SharePoint, or Planner.

However, a Microsoft 365 Group has a major caveat: it does not show up in the Outlook desktop app unless Cached Exchange Mode is enabled. Cached Exchange Mode is a feature that allows Outlook to store a copy of your mailbox data on your local computer, so that you can access it even when you are offline. Cached Exchange Mode can improve the performance and reliability of Outlook, but it can also cause some problems, especially with large inboxes. For example, Cached Exchange Mode can take up a lot of disk space, slow down Outlook, or corrupt the data file. To avoid these problems, you might have to disable Cached Exchange Mode for some users, or increase the PST file size limit using a registry edit. However, if you do that, you will not be able to see the Microsoft 365 Group calendar in the Outlook desktop app, which can be inconvenient for some users.

A possible alternative

So, is there any other solution that can meet your needs for a company-wide calendar with shared categories in Outlook? One possible alternative is to use a third-party app or service that can integrate with Outlook and provide the features that you are looking for. For example, you can use a cloud-based calendar service, such as Google Calendar or Calendly, that can sync with Outlook and allow you to create and share calendars with multiple users. You can also use a calendar management app, such as CalendarBridge or SyncGene, that can connect multiple calendars from different sources and platforms, and enable you to share categories across them. These apps or services might have different pricing plans, features, and limitations, so you will have to do some research and comparison to find the best one for your situation.

Conclusion

Creating a company-wide calendar with shared categories in Outlook can be challenging, as the native options in Outlook have some limitations or drawbacks that might not suit your requirements. However, you can explore some possible alternatives, such as using a third-party app or service that can integrate with Outlook and provide the features that you are looking for. Hopefully, this article has given you some insights and suggestions on how to create a company-wide calendar with shared categories in Outlook. If you have any questions or feedback, please feel free to leave a comment below. Thank you for reading.