I had been asked to update all users calendar permission to allow a certain application to be able to edit users calendar so it can automate adding days off and other calendar items.
Currently the only way this can be done that I know off is either using PowerShell or using MS Graph.
In this post we will be going through how to report calendar permission for all users and how to bulk update. We will be using the exchange online PowerShell module.
Install-Module -Name ExchangeOnlineManagementTo get the list of mailboxes and permissions we will use two command Get-Mailbox and Get-MailboxFolderPermission. Then we will be formatting the results for export out to a CSV.
To get calendar permission we will need to add :\Calendar to after the UserPrincipalName.
First step is that we need to connect to Exchange Online using PowerShell.
Connect-ExchangeOnline
To get a single user’s permission use
Get-MailboxFolderPermission -Identity user@domain.com:\calendar 
To check for a specific users permission we can add the -user parameter.
To get all users permission we need to get a list of all users using Get-Mailbox and then loop through each user to get the permission.
## Get all users mailboxes
$Mailboxes = Get-Mailbox -ResultSize Unlimited | Select-Object UserPrincipalName
## Loop through each mailbox
foreach ($mailbox in $Mailboxes) {
## Get default user calendar permissions
Write-Warning "Checking Permission on $($mailbox.UserPrincipalName)"
Get-MailboxFolderPermission -Identity "$($mailbox.UserPrincipalName):\Calendar" |
Select-Object @{Name="UserPrincipalName";E={$mailbox.UserPrincipalName}},FolderName,User,AccessRights |
Export-Csv C:\temp\Office_365_Export\Calendar_Report\CalenarPermissionReport.csv -NoTypeInformation -Append
}The export should look like the below.
Once I had a report of the current users calendar permission, I needed to add the user account that the application would use to add the calendar items.
To add calendar permission we use the Add-MailboxFolderPermission,
The roles that are available, along with the permissions that they assign are below.
- Author: CreateItems, DeleteOwnedItems, EditOwnedItems, FolderVisible, ReadItems
- Contributor: CreateItems, FolderVisible
- Editor: CreateItems, DeleteAllItems, DeleteOwnedItems, EditAllItems, EditOwnedItems, FolderVisible, ReadItems
- None: FolderVisible
- NonEditingAuthor: CreateItems, FolderVisible, ReadItems
- Owner: CreateItems, CreateSubfolders, DeleteAllItems, DeleteOwnedItems, EditAllItems, EditOwnedItems, FolderContact, FolderOwner, FolderVisible, ReadItems
- PublishingEditor: CreateItems, CreateSubfolders, DeleteAllItems, DeleteOwnedItems, EditAllItems, EditOwnedItems, FolderVisible, ReadItems
- PublishingAuthor: CreateItems, CreateSubfolders, DeleteOwnedItems, EditOwnedItems, FolderVisible, ReadItems
- Reviewer: FolderVisible, ReadItems
To add a single user use the command below.
Add-MailboxFolderPermission -Identity user@domain.com:\calendar -User "Account to be added" -AccessRights Editor I also wanted to be able to run this script again and not have to modify users that already have the correct permission as this will return an error, so we will be using a if statement to only apply to users who don’t have the permission.
Below is the full script.
## Calendar Permission Variable
$Account = "Account to be added"
## Get all users mailboxes
$Mailboxes = Get-Mailbox -ResultSize Unlimited | Select-Object UserPrincipalName
## Loop through each mailbox
foreach ($mailbox in $Mailboxes) {
## Get default user calendar permissions
$permission = Get-MailboxFolderPermission -Identity "$($mailbox.UserPrincipalName):\Calendar"
## Report on Users without correct calendar permissions and set permissions
if ($permission.User.DisplayName -notcontains $Account) {
Write-Warning "Calender permission not set on $($mailbox.UserPrincipalName) adding Permission"
Add-MailboxFolderPermission -Identity "$($mailbox.UserPrincipalName):\Calendar" -User $Account -AccessRights Editor | Out-Null
}
## calendar permission are correct
else {Write-Host "Calender Permission are set on $($mailbox.UserPrincipalName)" -ForegroundColor Green}
}
To read an XML report in PowerShell you can use the typecast to XML by using [xml] in front of the variable which should make querying the content easier. 
This is what the export will look like.
Once the script has completed there will be a result csv and if there are any non responding devices there will be a second csv. 
The export result will look like the below. 
To remove the WINS IP and set NetBios option, we will use the set method in the WMI class.
Once the script has run WINS should be removed and NetBios over Tcpip should be disabled this can be checked under the advanced properties on the NIC.
TheSleepyAdmins 