ExtendedPropertyDefinition declaration for EmailMessage in Powershell throws exception

Question

since I got to know that ExtendedProperties have its limit for a specific mailbox in the EWS cloud I am trying to switch up my code to have only one ExtendedProperty and just change its value each time I am assigning the property to an e-mail message I am sending to then find it and work on the e-mail message object later on in the program.

I am having a hard time setting this up correctly even though I am following the docs, but it just seems to not work out for me.

This is the code part that throws an Exception: "Multiple ambigious overloads found for "ExtendedPropertyDefinition" and the argument count "3" :

# email declaration exposing the $email object
.
.
.
# property declaration and setting the value

# since I want to have only one extended property, this is actually a valid GUID string that I then # convert to a Guid type
$GUIDproperty = "00000000-0000-0000-0000-000000000000"
$propertyGUID = [Guid]$GUIDproperty
# since I want to have a unique value each time set to the existing extended property
$propertyValue = [guid]::NewGuid().ToString()
$propertyName = "Id"
$ExtendedProperty = [Microsoft.Exchange.WebServices.Data.ExtendedPropertyDefinition]::new($propertyGUID, $propertyName, $propertyType)
# well I dont even reach this part, but just for the big picture
$email.SetExtendedProperty($ExtendedProperty, $propertyValue)

The docs I have followed for that are the following:

https://learn.microsoft.com/en-us/dotnet/api/microsoft.exchange.webservices.data.extendedpropertydefinition.-ctor?view=exchange-ews-api#microsoft-exchange-webservices-data-extendedpropertydefinition-ctor(microsoft-exchange-webservices-data-defaultextendedpropertyset-system-string-microsoft-exchange-webservices-data-mapipropertytype)

https://learn.microsoft.com/en-us/dotnet/api/microsoft.exchange.webservices.data.folder.setextendedproperty?redirectedfrom=MSDN&view=exchange-ews-api#Microsoft_Exchange_WebServices_Data_Folder_SetExtendedProperty_Microsoft_Exchange_WebServices_Data_ExtendedPropertyDefinition_System_Object_

https://learn.microsoft.com/en-us/dotnet/api/system.guid?view=net-7.0

Answer 1

The following works okay for me

$propertyType = [Microsoft.Exchange.WebServices.Data.MapiPropertyType]::String
$GUIDproperty = "82e3d64f-e26d-4321-8fc3-c31aa790197c"
$propertyGUID = [Guid]$GUIDproperty
$propertyValue = [guid]::NewGuid().ToString()
$propertyName = "MyPropId"
$ExtendedProperty = [Microsoft.Exchange.WebServices.Data.ExtendedPropertyDefinition]::new($propertyGUID, $propertyName, $propertyType)
return $ExtendedProperty

You don't specify what you using in the $propertyType so that maybe it, could also be to do with the versions you using. What version of PowerShell and the EWS Managed API are you trying ?