IMAP pst file import problems – folders containing IMAP items (IPF.Imap) type are not displayed in Exchange 2010 / 2013 OWA

Problem description

I have been solving problem in my friends Exchange 2013 environment. After migration (from IMAP profile) some folders were not visible in his OWA while those were visible in Outlook.
After research I have found, that every folder is “Different in properties” as seen in result Picture below.

wrong properties

Hmm, what now? I dont wanna use MFCMapi, since my friend has many folders. EWS? OK, but how?



  • As far as I understand Exchange, there are several kind of permissions and properties and mailbox folder properties belong to MAPI and those can be edited via MFC Mapi (ExFolders) ( or via EWS Managed API (
  • Yes. Exchange Web Services Managed API allows you to write custom applications, but I am not a programmer. I have downloaded a script from (, which I want to say thanks for and made additions to it.
  • Behind the scenes I have found nice technet discussion about how to change folder class so, that it will be visible in OWA, because OWA doesnt show folders with IMAP items. The goal is to change IPF.Imap class to IPF.Note. After changing via EWS you will see the diference as in picture below and after refresh OWA will work as needed.

Correct properties

  • As administrator I am not keen in C# so I will use my domain. Powershell (3.0) as I do the script on Exchange 2013 server


  • Before you even start to play with EWS, you need to install EWS Managed API fom the link: or newer version (Link is from Fall 2012)
  • After downloading install it to directory, from which you run the script. Note, that you will need to make reference for “Microsoft.Exchange.WebServices.dll” which is key component of EWS managed API. Example from my script is below:

$dllpath =“d:ExchangeScriptsEWSmanagedAPIMicrosoft.Exchange.WebServices.dll”  

  • Next step is to add your user name full access to mailbox, which will be checked and impersonate role, which will allow impersonation of mailbox under your user as you were owner of the mailbox. Commands are as follows:

New-ManagementRoleAssignment -Name Impersonation -User administrator -Role ApplicationImpersonation


Script can be downloaded from Skydrive

$dllpath = "d:ExchangeScriptsEWSmanagedAPIMicrosoft.Exchange.WebServices.dll" #Define DLL Path

[void][Reflection.Assembly]::LoadFile($dllpath) #Load DLL

$service = New-Object Microsoft.Exchange.WebServices.Data.ExchangeService([Microsoft.Exchange.WebServices.Data.ExchangeVersion]::Exchange2010_SP2) #Define EWS Service and version

$service.Url = New-Object System.Uri("") #Define uri for EWS VDir

$MBXID = "mailbox.identity" #Define mailboxID

foreach ($MailboxIdentity in $MBXID) {

Write-Host "Searching for $MailboxIdentity"

$MailboxName = (Get-Mailbox -Identity $MailboxIdentity).PrimarySmtpAddress.ToString()

$MailboxDName = (Get-Mailbox -Identity $MailboxIdentity).DisplayName

$ImpersonatedUserId = New-Object Microsoft.Exchange.WebServices.Data.ImpersonatedUserId -ArgumentList ([Microsoft.Exchange.WebServices.Data.ConnectingIdType]::SmtpAddress),$MailboxName #Define impersonation

$service.ImpersonatedUserId = $ImpersonatedUserId #Impersonate service under userID

$folderid = new-object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::Root,$MailboxName) #MsgFolderRoot selection and creation of new root folder object

$f1 = [Microsoft.Exchange.WebServices.Data.Folder]::Bind($service, $MailboxName) #Binding folder under mailbox identity

$fold = get-mailboxfolderstatistics $MailboxIdentity #Getting complete list of selected mailbox

foreach ($mbxfolder in $fold){

#Define Folder View Really only want to return one object

$fvFolderView = new-object Microsoft.Exchange.WebServices.Data.FolderView(100) #page size for displayed folders

$fvFolderView.Traversal = [Microsoft.Exchange.WebServices.Data.FolderTraversal]::Deep; #Search traversal selection Deep = recursively

#Define a Search folder that is going to do a search based on the DisplayName of the folder

$SfSearchFilter = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+IsEqualTo([Microsoft.Exchange.WebServices.Data.FolderSchema]::Displayname,$ #for each folder in mailbox define search

$findFolderResults = $service.FindFolders($folderid,$SfSearchFilter,$fvFolderView) #for each folder in mailbox define folder view (this is online task for store.exe) and perform search

if ($findFolderResults.TotalCount -eq 0){ "Folder Doesn't Exist" } #Info if folder still exist

else {"Folder Exist"

ForEach ($Folder in $findFolderResults.Folders) { #for each folder in folder results perform check of folder class

$folder.folderclass #Info about folder class

if ($Folder.folderclass -eq "IPF.Imap"){ #If folder class is target type, do change and update

$Folder.folderclass = "IPF.Note" #Folder class change in variable

Write-Host "Updating folder $ to correct type IPF.Note. Folder will start to be visible in OWA"

$Folder.update() #Folder class update in mailbox via EWS






The script will generate some output to host:

converting via script