From 77b6e4398d3fe692cbdbe05c59e459deec197ff9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Petr=20=C5=A0t=C4=9Bp=C3=A1n?= <petr@stepan.tech>
Date: Tue, 21 Jul 2026 15:25:01 +0200
Subject: [PATCH] Add Set-RoomMailboxPermission script to configure calendar
 permissions and processing settings for room mailboxes

---
 Set-RoomMailboxPermission.ps1 | 110 ++++++++++++++++++++++++++++++++++
 1 file changed, 110 insertions(+)
 create mode 100644 Set-RoomMailboxPermission.ps1

diff --git a/Set-RoomMailboxPermission.ps1 b/Set-RoomMailboxPermission.ps1
new file mode 100644
index 0000000..d1781f4
--- /dev/null
+++ b/Set-RoomMailboxPermission.ps1
@@ -0,0 +1,110 @@
+<#
+.SYNOPSIS
+    Configures calendar permissions and processing settings on the specified room mailboxes.
+
+.DESCRIPTION
+    For each mailbox identity supplied (directly or via the pipeline):
+      - Grants the Default user LimitedDetails access on the mailbox calendar
+        folder.
+      - Configures calendar processing so the organizer's name is added to the
+        meeting subject, and neither comments nor the subject are stripped
+        from booking requests.
+
+    Requires an existing Exchange Online session (Connect-ExchangeOnline) -
+    this script does not connect or disconnect itself.
+
+.PARAMETER Identity
+    One or more room mailbox identities (UPN, email address, or Exchange
+    Identity) to configure. Accepts pipeline input, e.g. piped straight from
+    Get-Mailbox.
+
+.PARAMETER CalendarFolderName
+    Name of the mailbox's Calendar folder, in the mailbox's own language.
+    Defaults to "Calendar" (English). Use this for non-English mailboxes, e.g.
+    "Kalendar" for Czech. The actual name for a given mailbox can be listed
+    with:
+    Get-MailboxFolderStatistics -Identity <Identity> -FolderScope Calendar | Where-Object { $_.FolderType -eq 'Calendar' } | Select-Object Name
+
+.EXAMPLE
+    .\Set-RoomMailboxPermission.ps1 -Identity room1@contoso.com
+    Configures a single room mailbox.
+
+.EXAMPLE
+    Get-Mailbox -ResultSize Unlimited | Where-Object { $_.ResourceType -eq 'Room' } | .\Set-RoomMailboxPermission.ps1
+    Configures every room mailbox in the tenant, piped in from Get-Mailbox.
+
+.EXAMPLE
+    Get-Mailbox -ResultSize Unlimited | Where-Object { $_.ResourceType -eq 'Room' } | .\Set-RoomMailboxPermission.ps1 -WhatIf
+    Shows which room mailboxes would be changed without applying anything.
+
+.EXAMPLE
+    .\Set-RoomMailboxPermission.ps1 -Identity room-cz@contoso.com -CalendarFolderName 'Kalendar'
+    Configures a Czech-locale room mailbox whose Calendar folder is named "Kalendar".
+
+.NOTES
+    Author:   Petr Stepan
+    Created:  2026-07-21
+    Version:  1.0.0
+    Changelog:
+        1.0.0 - Initial version
+
+    Requires the ExchangeOnlineManagement module, an active Exchange Online
+    session, and an account with permission to manage mailbox folder
+    permissions and calendar processing.
+#>
+
+#Requires -Modules ExchangeOnlineManagement
+[CmdletBinding(SupportsShouldProcess = $true, ConfirmImpact = 'Medium')]
+param (
+    [Parameter(Mandatory = $true, ValueFromPipeline = $true, ValueFromPipelineByPropertyName = $true, HelpMessage = 'Room mailbox identity (UPN, email, or Exchange Identity) to configure.')]
+    [ValidateNotNullOrEmpty()]
+    [string[]]
+    $Identity,
+
+    [Parameter(Mandatory = $false, HelpMessage = 'Name of the Calendar folder in the mailbox locale.')]
+    [ValidateNotNullOrEmpty()]
+    [string]
+    $CalendarFolderName = 'Calendar'
+)
+
+begin {
+    Set-StrictMode -Version Latest
+    $ErrorActionPreference = 'Stop'
+
+    $processedCount = 0
+    $failedCount = 0
+}
+
+process {
+    foreach ($id in $Identity) {
+        $processedCount++
+
+        if ($PSCmdlet.ShouldProcess($id, "Set calendar folder permission (LimitedDetails) and calendar processing settings")) {
+            try {
+                Set-MailboxFolderPermission -Identity "$($id):\$CalendarFolderName" -User Default -AccessRights LimitedDetails -ErrorAction Stop
+
+                Set-CalendarProcessing -Identity $id -AddOrganizerToSubject $true -DeleteComments $false -DeleteSubject $false -ErrorAction Stop
+
+                Write-Verbose "Configured '$id' successfully."
+            }
+            catch {
+                Write-Warning "Failed to configure '$id': $_"
+                $failedCount++
+            }
+        }
+    }
+}
+
+end {
+    if ($processedCount -eq 0) {
+        Write-Warning "No mailboxes were provided."
+        exit 0
+    }
+
+    if ($failedCount -gt 0) {
+        Write-Warning "$failedCount of $processedCount mailboxes failed to configure."
+        exit 1
+    }
+
+    exit 0
+}