To give yourself or another user full access to someone else’s mailbox in Office 365 you have to use powershell. It can’t be done online.
In this example we are going to give Pieter full access to the mailbox of Danielle use this command:
Add-MailboxPermission Danielle@kops-ict.nl -User Pieter@kops-ict.nl -AccessRights FullAccess
As an alternative you can also give permissions to an inbox only
Here’s the code:
Add-MailboxFolderPermission -Identity Danielle@kops-ict.nl:\Inbox -User Pieter@kops-ict.nl -AccessRights Owner
For more detailed information, please refer below article:
Give an Administrator the Ability to Open and View the Contents of a User’s Mailbox(http://help.outlook.com/en-us/140/gg709759.aspx )
In Office 365 you can open another user’s mailbox. Here’s how.
Go to the outlook web access page. In the left column find your username and right click on it.
Then select “Other user’s inbox”
In the dialog box that appears, enter the name of the desired mailbox or use the addressbook icon to do a full search.
And click OK. Now you will see the other user’s mailbox appear in the left column.
When you receive an error stating that you have no permission to open the inbox when you are sure it exists, you may need to get the right permissions from your administrator.
I also have an article that explains how to set the right permissions.
Read it here.
I found a great article the explains how to add an image slider with a search results web part.
You can read the article here.
Thanks to Yohan Belval