This question is further to a thread I started last week regarding a distribution list created via EWS not being editable in OWA. I found that if I added the property 0x3016 = True it would then work. Now my task is to go through all previously created DLs (that don't have this property) and add the property. I am doing this via UpdateItem. I get no error, but it does not work - the new property is not added. Below is an example of the XML I am using. Any ideas?
<UpdateItem MessageDisposition="SaveOnly" ConflictResolution="AutoResolve" xmlns="http://schemas.microsoft.com/exchange/services/2006/messages" xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types"><ItemChanges><t:ItemChange><t:ItemId Id="AAMkADNjNjA1MTIxLWNlNmItNDBjMS04NWE0LTQ3ZmM0YTFiMTg4MABGAAAAAADzAjMnWlbcRo51UWjY2+udBwBtGm0AIaIyTp7trMMKSGyiAAAAzNL1AACxNOWmTuGVSbP5Z2FuqVoaAABiuTUZAAA=" ChangeKey="EgAAABYAAACxNOWmTuGVSbP5Z2FuqVoaAABiue7T"/><t:Updates><t:SetItemField><t:ExtendedFieldURI PropertyTag="0x3016" PropertyType="Boolean"/><t:Contact><t:ExtendedProperty><t:ExtendedFieldURI PropertyTag="0x3016" PropertyType="Boolean"/><t:Values><t:Value>true</t:Value></t:Values></t:ExtendedProperty></t:Contact></t:SetItemField></t:Updates></t:ItemChange></ItemChanges></UpdateItem>