How to share your mailbox with a colleague in Outlook (Office365)

When using Office365 you have the ability to share your mailbox with a named colleague and can specify whether they have view only access or can act on your behalf i.e. deleting or replying to messages. You will be required to specify which folders are shared so please remember to set permissions against your inbox folder and also any relevant subfolders therein, sent and deleted items etc.

Using outlook online (signed in from the website office.com)

Right click against your Inbox folder and open the Permissions settings as below:

Click the + sign and search for the colleague who you wish to share your mailbox with
Once their name appears in the box make sure it is highlighted and select the required Permission level i.e. Editor, Reviewer, None
Check the required permission options are selected under “Read” “Write” “Delete Access” and “Other” then click OK:

Repeat the above for each of the folders you wish to share (different permission options may be appropriate for each folder)
Once permissions are set your colleague will need to add the folders you shared in their own outlook online (or desktop installed outlook)
In outlook online this can be done by right clicking against “Folders” and select “Add a shared folder” then search your name and click “Add” to pull in your mailbox folders underneath their own in outlook.
If the colleague is using installed desktop outlook 365 they will find the options to add your mailbox folders under their File – account settings – (double click their mail account) – more settings – Advanced – Add – (search YOUR name in the box to add mailbox) – Apply – OK – Next – Done – Close

Sharing your mailbox from installed desktop version of outlook 365

Right click against your email address above the folders list on the left of your outlook screen – go to “Folder permissions”

Click “Add” and search for the person you wish to share your mailbox with from Global Address Book then highlight their name and click “Add”
Click “OK”
Now your colleagues’ name should appear in the box you will need to select the required Permission level and review the “Read” “Write” “Delete Access” and “Other” settings then click “Apply” and OK:
It is required that you follow the next steps for each folder you wish to share:
Right click against a folder e.g. Inbox
Go to “Properties”
In the permissions tab – add a named contact to the box, review permission level and the the “Read” “Write” “Delete Access” and “Other” settings then click “Apply” and OK:

Once permissions are set your colleague will need to add the folders you shared in their own outlook online (or desktop installed outlook)
In outlook online this can be done by right clicking against “Folders” and select “Add a shared folder” then search your name and click “Add” to pull in your mailbox folders underneath their own in outlook.
If the colleague is using installed desktop outlook 365 they will find the options to add your mailbox folders under their File – account settings – (double click their mail account) – more settings – Advanced – Add – (search YOUR name in the box to add mailbox) – Apply – OK – Next – Done – Close