Hi Rebecca Teasdale,
Good day! Thanks for posting in the Microsoft Community. We are happy to assist you.
To better assist you, could you please clarify if you are aglobal or Exchange administrator in your organization? This information will help us provide you with the most relevant guidance.
If you are an administrator, you can grant access to an employee’s email account through the Microsoft 365 Admin Center:
Go to the Microsoft 365 Admin Center: admin.microsoft.com > Navigate to Users > Select Users > Active users. > Select the User. >Choose the user whose email account you need to access. > Go to the Mail tab > Mailbox permissions. > Grant Access: > Add yourself (or another user) and specify the type of access (e.g., Full Access, Send As, Send on Behalf).
You can also do that in the Exchange admin center Manage permissions for recipients in Exchange Online.
If you are not an administrator, you will need the employee to grant you delegate access to their mailbox. This allows you to manage their email and calendar without needing direct access to their account. They can follow the steps in this guide to grant delegate access: Allow someone else to manage your mail and calendar.
Please note it is advised to Follow your Company Policies (Ensure that you comply with your organization’s policies regarding email access.) and or to Inform the Employee: It’s advisable to inform the employee about this access unless there is a specific reason not to, and to always follow your company's protocols.
We are looking forward to your response! Thanks for your precious time. Have a nice day!
Best regards,
Microsoft Community Moderator