Opening a Shared Calendar

Hi @Christine Brady,

Welcome to the Microsoft Q&A forum.

Thank you for contacting us. Based on the information you provided, I would like to share the following details:

First, I would like to ask whether the account you are using to open the calendar and your colleague’s account belong to the same tenant (for example, if they share the same domain: @company.com).

Additionally, you can ask your colleague to check whether they have granted you the necessary sharing permissions.

You can provide your colleague with the following resource, which explains how to check depending on the Outlook application they are using:https://support.microsoft.com/en-us/office/share-and-access-a-calendar-with-edit-or-delegate-permissions-in-outlook-532e6410-ee80-42b5-9b1b-a09345ccef1b

I’ve sent you a message in PM, please check it when you can.

If you have any updates regarding the issue or any other questions, please feel free to share them with me. I’ll be happy to assist you.

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