Is it possible to delete extended properties without knowing the id?

Question

Hello,
Can you delete any custom extended properties without knowing their ID?
I took over managing a feature that used EWS to send emails to customers.The current code creates a new GUID, and thus new Extended Property, every time an email is sent.
// Create a custom extended property and add it to the message.
var myExtendedPropertyDefinition = new ExtendedPropertyDefinition(Guid.NewGuid(), "MyGuidId", MapiPropertyType.String);
mail.SetExtendedProperty(myExtendedPropertyDefinition, "MyGuidId");
// Send and save a copy
mail.SendAndSaveCopy();
Is there a way to delete any of the custom extended propeties without knowing the IDs?
Thank you

Answer 1

No you can't do that in EWS you need to know the details of the property you want to Read/Write or delete. EWS has no method of enumerating all extended properties either you would need to use MAPI to do this.
>>The current code creates a new GUID, and thus new Extended Property, every time an email is sent.
 I'd question the design of this what where they trying to acheive ? Why not have ths same property with a different Value ? else using an X-header would be better idea at least then it will persist ouside of your Exchange infrastructure and even
inside would be more discoverable.
Cheers
Glen