EWS Basics : Create a Folder in a Mailbox or Public Folder

One of the more common questions on EWS I get is around how to create a folder so this post will cover the basics you need to know around creating folders using EWS in Mailboxes or Public Folders.

What you need to create a Folder

To create a folder you first need a unique name for the new folder eg if you going to create a folder called "SubFolder1" under the Inbox another folder with the name Subfolder1 can't already exists as a SubFolder of the Inbox (anywhere else in the Mailbox is okay) if it does you will get an error.  So when writing a script to create a folder its first good to includes a search to see if the folder already exists. eg

  #Define Folder Veiw Really only want to return one object  
  $fvFolderView = new-object Microsoft.Exchange.WebServices.Data.FolderView(1)  
  #Define a Search folder that is going to do a search based on the DisplayName of the folder  
  $SfSearchFilter = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+IsEqualTo([Microsoft.Exchange.WebServices.Data.FolderSchema]::DisplayName,$NewFolderName)  
  #Do the Search  
  $findFolderResults = $service.FindFolders($EWSParentFolder.Id,$SfSearchFilter,$fvFolderView)  
  if ($findFolderResults.TotalCount -eq 0){  
      Write-host ("Folder Doesn't Exist")  
   $NewFolder.Save($EWSParentFolder.Id)  
   Write-host ("Folder Created")  
  }  
  else{  
      Write-error ("Folder already Exist with that Name")  
  }  

The second piece of information you need is what type of folder your going to create, in Exchange  folders have a default ItemType property (in EWS this the FolderClass in Mapi its PR_CONTAINER_CLASS) . Eg when you create a folder is you specify the Folder Class of this Folder is for Appointment the Client will treat that folder as a Calender Folder. In EWS once this FolderClass is set the service will return a different FolderType for the following Folder

• Mail Folders - IPF.Note - EWS Managed API Type Folder
• Calendar Folders - IPF.Appointment - EWS Managed API Type CalendarFolder
• Contact Folders - IPF.Contact - EWS Managed API Type ContactFolder
• Task Folders - IPF.Task - EWS Managed API Type TaskFolder

In Exchange and Outlook there are other FolderType eg Notes, Journal etc but these will just be returned as Folder in EWS. Generally apart from CalendarFolder which has different Permissions types the Folders can be treated the same apart from the FolderClass property.

The last piece of information you need when creating a folder is you need know the ewsId of the Parent folder. If your creating a folder within a WellKnown Folder like the Inbox,Calendar,MailboxRoot etc then you can just use the FolderId overload eg for the Inbox

$folderid= new-object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::Inbox,$MailboxName)   
$NewFolder.Save($folderid)

If this is not a WellKnownFolder or a PublicFolder then you need to first find the EWSFolderId, for this I generally recommend you great a path for the parent folder like \Inbox\ParentFolder and then use a Function like this to find the FolderId eg

function FolderIdFromPath{
 param (
         $FolderPath = "$( throw 'Folder Path is a mandatory Parameter' )",
   $SmtpAddress = "$( throw 'Folder Path is a mandatory Parameter' )"
    )
 process{
  ## Find and Bind to Folder based on Path  
  #Define the path to search should be seperated with \  
  #Bind to the MSGFolder Root  
  $folderid = new-object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::MsgFolderRoot,$SmtpAddress)   
  $tfTargetFolder = [Microsoft.Exchange.WebServices.Data.Folder]::Bind($service,$folderid)  
  #Split the Search path into an array  
  $fldArray = $FolderPath.Split("\") 
   #Loop through the Split Array and do a Search for each level of folder 
  for ($lint = 1; $lint -lt $fldArray.Length; $lint++) { 
         #Perform search based on the displayname of each folder level 
         $fvFolderView = new-object Microsoft.Exchange.WebServices.Data.FolderView(1) 
         $SfSearchFilter = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+IsEqualTo([Microsoft.Exchange.WebServices.Data.FolderSchema]::DisplayName,$fldArray[$lint]) 
         $findFolderResults = $service.FindFolders($tfTargetFolder.Id,$SfSearchFilter,$fvFolderView) 
         if ($findFolderResults.TotalCount -gt 0){ 
             foreach($folder in $findFolderResults.Folders){ 
                 $tfTargetFolder = $folder                
             } 
         } 
         else{ 
             "Error Folder Not Found"  
             $tfTargetFolder = $null  
             break  
         }     
     }  
  if($tfTargetFolder -ne $null){
   return $tfTargetFolder.Id.UniqueId.ToString()
  }
  else{
   throw "Folder not found"
  }
 }
}

or for Public Folders you need to use something like

function PublicFolderIdFromPath{
 param (
            [Parameter(Position=0, Mandatory=$true)] [Microsoft.Exchange.WebServices.Data.ExchangeService]$service,
            [Parameter(Position=1, Mandatory=$true)] [String]$FolderPath,
            [Parameter(Position=2, Mandatory=$true)] [String]$SmtpAddress
    )
 process{
  ## Find and Bind to Folder based on Path  
  #Define the path to search should be seperated with \  
  #Bind to the MSGFolder Root  
  $folderid = new-object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::PublicFoldersRoot)   
        $psPropset= new-object Microsoft.Exchange.WebServices.Data.PropertySet([Microsoft.Exchange.WebServices.Data.BasePropertySet]::FirstClassProperties)
        $PR_REPLICA_LIST = New-Object Microsoft.Exchange.WebServices.Data.ExtendedPropertyDefinition(0x6698,[Microsoft.Exchange.WebServices.Data.MapiPropertyType]::Binary); 
        $psPropset.Add($PR_REPLICA_LIST)
  $tfTargetFolder = [Microsoft.Exchange.WebServices.Data.Folder]::Bind($service,$folderid,$psPropset)  
        $PR_REPLICA_LIST_Value = $null
        if($tfTargetFolder.TryGetProperty($PR_REPLICA_LIST,[ref]$PR_REPLICA_LIST_Value)){
                 $GuidAsString = [System.Text.Encoding]::ASCII.GetString($PR_REPLICA_LIST_Value, 0, 36);
                 $HeaderAddress = new-object System.Net.Mail.MailAddress($service.HttpHeaders["X-AnchorMailbox"])
                 $pfHeader = $GuidAsString + "@" + $HeaderAddress.Host
                 write-host ("Root Public Folder Routing Information Header : " + $pfHeader )  
                 $service.HttpHeaders.Add("X-PublicFolderMailbox", $pfHeader)    
        }
  #Split the Search path into an array  
  $fldArray = $FolderPath.Split("\") 
   #Loop through the Split Array and do a Search for each level of folder 
  for ($lint = 1; $lint -lt $fldArray.Length; $lint++) { 
         #Perform search based on the displayname of each folder level 
         $fvFolderView = new-object Microsoft.Exchange.WebServices.Data.FolderView(1) 
            $fvFolderView.PropertySet = $psPropset
         $SfSearchFilter = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+IsEqualTo([Microsoft.Exchange.WebServices.Data.FolderSchema]::DisplayName,$fldArray[$lint]) 
         $findFolderResults = $service.FindFolders($tfTargetFolder.Id,$SfSearchFilter,$fvFolderView) 
         if ($findFolderResults.TotalCount -gt 0){ 
             foreach($folder in $findFolderResults.Folders){ 
                 $tfTargetFolder = $folder                
             } 
         } 
         else{ 
             "Error Folder Not Found"  
             $tfTargetFolder = $null  
             break  
         }     
     }  
  if($tfTargetFolder -ne $null){
            $PR_REPLICA_LIST_Value = $null
            if($tfTargetFolder.TryGetProperty($PR_REPLICA_LIST,[ref]$PR_REPLICA_LIST_Value)){
                    $GuidAsString = [System.Text.Encoding]::ASCII.GetString($PR_REPLICA_LIST_Value, 0, 36);
                    $HeaderAddress = new-object System.Net.Mail.MailAddress($service.HttpHeaders["X-AnchorMailbox"])
                    $pfHeader = $GuidAsString + "@" + $HeaderAddress.Host
                    write-host ("Target Public Folder Routing Information Header : " + $pfHeader )  
                    Get-PublicFolderContentRoutingHeader -service $service -Credentials $Credentials -MailboxName $SmtpAddress -pfAddress $pfHeader
            }            
   return $tfTargetFolder.Id.UniqueId.ToString()
  }
  else{
   throw "Folder not found"
  }
 }
}

I have a module that combines all these that I've blogged before here https://github.com/gscales/Powershell-Scripts/blob/master/CreateFolder.ps1 I've added a new cmdlet in this module to now allow you to create folder within a public folder eg

Create-PublicFolder -Mailboxname mailbox@domain.com -NewFolderName test -ParentPublicFolderPath '\Folder1\Folder2'