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Create a Public Folder (or Mailbox folder) Post using EWS and Powershell

Somebody asked a couple of weeks ago about creating Post Items using EWS and Powershell which I haven't posted a sample for previously. Given its the first day of the year an example of a post about how to create a post to wish everybody happy new year seems like good idea.

Creating a POST item using the EWS Managed API is pretty straight forward as their is a PostItem Class you can use. To create a post is a folder you just need to know the ewsID of the folder you want to create the POST in. So in EWS you need some code that will either search and find the Folder in the Mailbox you want to post to or the Public Folder you want to post to.  I've created two sample one show how to create a post in Mailbox folders and the other in a Public folder. I've posted a download of the two sample here . The code for creating a POST in a Public folder looks like

  1. ## Get the Mailbox to Access from the 1st commandline argument  
  2.   
  3. $MailboxName = $args[0]  
  4.   
  5. ## Load Managed API dll    
  6. Add-Type -Path "C:\Program Files\Microsoft\Exchange\Web Services\2.0\Microsoft.Exchange.WebServices.dll"    
  7.     
  8. ## Set Exchange Version    
  9. $ExchangeVersion = [Microsoft.Exchange.WebServices.Data.ExchangeVersion]::Exchange2010_SP2    
  10.     
  11. ## Create Exchange Service Object    
  12. $service = New-Object Microsoft.Exchange.WebServices.Data.ExchangeService($ExchangeVersion)    
  13.     
  14. ## Set Credentials to use two options are availible Option1 to use explict credentials or Option 2 use the Default (logged On) credentials    
  15.     
  16. #Credentials Option 1 using UPN for the windows Account    
  17. $psCred = Get-Credential    
  18. $creds = New-Object System.Net.NetworkCredential($psCred.UserName.ToString(),$psCred.GetNetworkCredential().password.ToString())    
  19. $service.Credentials = $creds        
  20.     
  21. #Credentials Option 2    
  22. #service.UseDefaultCredentials = $true    
  23.     
  24. ## Choose to ignore any SSL Warning issues caused by Self Signed Certificates    
  25.     
  26. ## Code From http://poshcode.org/624  
  27. ## Create a compilation environment  
  28. $Provider=New-Object Microsoft.CSharp.CSharpCodeProvider  
  29. $Compiler=$Provider.CreateCompiler()  
  30. $Params=New-Object System.CodeDom.Compiler.CompilerParameters  
  31. $Params.GenerateExecutable=$False  
  32. $Params.GenerateInMemory=$True  
  33. $Params.IncludeDebugInformation=$False  
  34. $Params.ReferencedAssemblies.Add("System.DLL") | Out-Null  
  35.   
  36. $TASource=@' 
  37.   namespace Local.ToolkitExtensions.Net.CertificatePolicy{ 
  38.     public class TrustAll : System.Net.ICertificatePolicy { 
  39.       public TrustAll() {  
  40.       } 
  41.       public bool CheckValidationResult(System.Net.ServicePoint sp, 
  42.         System.Security.Cryptography.X509Certificates.X509Certificate cert,  
  43.         System.Net.WebRequest req, int problem) { 
  44.         return true; 
  45.       } 
  46.     } 
  47.   } 
  48. '@   
  49. $TAResults=$Provider.CompileAssemblyFromSource($Params,$TASource)  
  50. $TAAssembly=$TAResults.CompiledAssembly  
  51.   
  52. ## We now create an instance of the TrustAll and attach it to the ServicePointManager  
  53. $TrustAll=$TAAssembly.CreateInstance("Local.ToolkitExtensions.Net.CertificatePolicy.TrustAll")  
  54. [System.Net.ServicePointManager]::CertificatePolicy=$TrustAll  
  55.   
  56. ## end code from http://poshcode.org/624  
  57.     
  58. ## Set the URL of the CAS (Client Access Server) to use two options are availbe to use Autodiscover to find the CAS URL or Hardcode the CAS to use    
  59.     
  60. #CAS URL Option 1 Autodiscover    
  61. $service.AutodiscoverUrl($MailboxName,{$true})    
  62. "Using CAS Server : " + $Service.url     
  63.      
  64. #CAS URL Option 2 Hardcoded    
  65.     
  66. #$uri=[system.URI] "https://casservername/ews/exchange.asmx"    
  67. #$service.Url = $uri      
  68.     
  69. ## Optional section for Exchange Impersonation    
  70.     
  71. #$service.ImpersonatedUserId = new-object Microsoft.Exchange.WebServices.Data.ImpersonatedUserId([Microsoft.Exchange.WebServices.Data.ConnectingIdType]::SmtpAddress, $MailboxName)   
  72.   
  73. function FolderIdFromPath{  
  74.     param (  
  75.             $FolderPath = "$( throw 'Folder Path is a mandatory Parameter' )"  
  76.           )  
  77.     process{  
  78.         ## Find and Bind to Folder based on Path    
  79.         #Define the path to search should be seperated with \    
  80.         #Bind to the MSGFolder Root    
  81.         $folderid = new-object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::PublicFoldersRoot)     
  82.         $tfTargetFolder = [Microsoft.Exchange.WebServices.Data.Folder]::Bind($service,$folderid)    
  83.         #Split the Search path into an array    
  84.         $fldArray = $FolderPath.Split("\")  
  85.          #Loop through the Split Array and do a Search for each level of folder  
  86.         for ($lint = 1; $lint -lt $fldArray.Length; $lint++) {  
  87.             #Perform search based on the displayname of each folder level  
  88.             $fvFolderView = new-object Microsoft.Exchange.WebServices.Data.FolderView(1)  
  89.             $SfSearchFilter = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+IsEqualTo([Microsoft.Exchange.WebServices.Data.FolderSchema]::DisplayName,$fldArray[$lint])  
  90.             $findFolderResults = $service.FindFolders($tfTargetFolder.Id,$SfSearchFilter,$fvFolderView)  
  91.             if ($findFolderResults.TotalCount -gt 0){  
  92.                 foreach($folder in $findFolderResults.Folders){  
  93.                     $tfTargetFolder = $folder                 
  94.                 }  
  95.             }  
  96.             else{  
  97.                 "Error Folder Not Found"   
  98.                 $tfTargetFolder = $null   
  99.                 break   
  100.             }      
  101.         }   
  102.         if($tfTargetFolder -ne $null){ 
  103.             return $tfTargetFolder.Id.UniqueId.ToString() 
  104.         } 
  105.     } 
  106. } 
  107. #Example use 
  108. $fldId = FolderIdFromPath -FolderPath "\aaaa\bbbb" 
  109. if($fldId -ne "Error Folder Not Found"){ 
  110.     $SubFolderId =  new-object Microsoft.Exchange.WebServices.Data.FolderId($fldId) 
  111.     $SubFolder = [Microsoft.Exchange.WebServices.Data.Folder]::Bind($service,$SubFolderId) 
  112.  
  113.     $NewPost = New-Object Microsoft.Exchange.WebServices.Data.PostItem -ArgumentList $service   
  114.     $NewPost.Subject = "Happy New Year"   
  115.     $NewPost.Body = New-Object Microsoft.Exchange.WebServices.Data.MessageBody   
  116.     $NewPost.Body.BodyType = [Microsoft.Exchange.WebServices.Data.BodyType]::HTML   
  117.     $NewPost.Body.Text = "Happy New Year" 
  118.     $NewPost.Save($SubFolder.Id)   
  119.     Write-Host ("Created Post")  
  120. }
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All sample scripts and source code is provided by for illustrative purposes only. All examples are untested in different environments and therefore, I cannot guarantee or imply reliability, serviceability, or function of these programs.

All code contained herein is provided to you "AS IS" without any warranties of any kind. The implied warranties of non-infringement, merchantability and fitness for a particular purpose are expressly disclaimed.