[E2010][EWSMA] Impersonation Configuration

Question

Hi
Exchange 2010 SP2
EWS API 2.0
I'm looking for specific advice regarding configuring of impersonation accounts and security groups.
Environment
We have a single Exchange 2010 production environment with 2 CAS servers in different domains. I have 3 environments development, QA and production that have WCF and Windows service that access Exchange and
act as an interface to Exchange to a back-end application also running in each environment. All environment services are running and accessing Exchange.
Current Impersonation Setup
A single impersonation account used in the services to impersonate in development, QA and production environments.
Three security groups that contain users to impersonate specific to each environment.
Three ManagementScope and ManagementRoleAssignment configured in Exchange, one for each environment/security group, all assigned to the single impersonation user account. Both QA and production services are running and accessing Exchange
Question
Is this a recommended configuration in this scenario?
3 environments, 3 security groups, 3 impersonation roles/scope to 1 impersonation user in 1 Exchange environment?
Issues
We seeing intermittent exceptions being raised by EWS 'access denied' on updating tasks and appointments for valid impersonation user accounts in the production services.
If anyone has any advice about this being a valid configuration, it would be very much appreciated.
Kind regards,
Lee

Answer 1

You should be able to use the Extended properties to work this out have a read of
http://msdn.microsoft.com/en-us/library/office/cc815707(v=office.15).aspx .
eg this should cover your case "For example, suppose John is receiving Sally's messages while Sally is on vacation. The PR_RCVD_REPRESENTING properties
identify John as the delegate recipient. When John sends a reply to a message that he has received for Sally, the message's PR_SENDER properties
identify John as the sender. Because John is representing Sally, the PR_SENT_REPRESENTING properties
identify Sally."
ExtendedPropertyDefinition PR_SENDER_NAME = new ExtendedPropertyDefinition(0x0C1A,MapiPropertyType.String);
ExtendedPropertyDefinition PR_SENT_REPRESENTING_NAME = new ExtendedPropertyDefinition(0x0042, MapiPropertyType.String);
PropertySet psPropSet = new PropertySet(BasePropertySet.FirstClassProperties) { PR_SENDER_NAME, PR_SENT_REPRESENTING_NAME };
Message.Load(psPropSet);
String PR_SENDER_NAMEval = "";
String PR_SENT_REPRESENTING_NAMEval = "";
if(Message.TryGetProperty(PR_SENDER_NAME,out PR_SENDER_NAMEval)){
Console.WriteLine(PR_SENDER_NAMEval);
if (Message.TryGetProperty(PR_SENT_REPRESENTING_NAME, out PR_SENT_REPRESENTING_NAMEval))
Console.WriteLine(PR_SENT_REPRESENTING_NAMEval);
Cheers
Glen