Exchange 2010 Unified communications voicemail not working

Hi

I’m currently in the process of moving our old Exchange 2010 sp2 server to a new Exchange 2010 SP3 system and we are running Lync 2013. I’ve moved all the mailbox’s over and all mail is working correctly but the problem I’ve having is getting Unified Communications to work on the new exchange server. I’ve removed the UM role from the old server.

Auto attendant picks up and I can transfer call with no problem. When I dial a user the voicemail picks up but when I leave a message no voicemail is delivered to the users mailbox.
I get the following 2 events in the event viewer

Event ID: 1423
Task Category: UMCore
Source: MSExchange Unified Messaging

Details:
The Unified Messaging server encountered an error while trying to process the message with header file "C:\Program Files\Microsoft\Exchange Server\V14\UnifiedMessaging\voicemail\d618e5d0-f3c8-40c2-989d-37739cebe1f3.txt". Error details: "Microsoft.Exchange.UM.UMCore.SmtpSubmissionException: Submission to the Hub Transport server failed. The operation will be retried. ---> Microsoft.Exchange.Net.ExSmtpClient.UnexpectedSmtpServerResponseException: Unexpected SMTP server response. Expected: 220, actual: 500, whole response: 500 5.3.3 Unrecognized command
 
   at Microsoft.Exchange.Net.ExSmtpClient.SmtpTalk.CheckResponse(ServerResponseInfo response, Int32 expectedCode)
   at Microsoft.Exchange.Net.ExSmtpClient.SmtpTalk.Command(SmtpChunk[] chunks, SmtpCommandType command, Int32 expectedCode)
   at Microsoft.Exchange.Net.ExSmtpClient.SmtpTalk.StartTls()
   at Microsoft.Exchange.Net.ExSmtpClient.SmtpClient.Submit(Boolean disableDelayedAck)
   at Microsoft.Exchange.UM.UMCore.SmtpSubmissionHelper.SubmitMessage(MessageItem message, String senderAddress, String recipientAddress, OutboundConversionOptions submissionConversionOptions, InternalExchangeServer smtpServer)
   at Microsoft.Exchange.UM.UMCore.SmtpSubmissionHelper.SubmitMessage(MessageItem message, String senderAddress, String recipientAddress, OutboundConversionOptions submissionConversionOptions, String requestId)
   --- End of inner exception stack trace ---

Server stack trace:
   at Microsoft.Exchange.UM.UMCore.SmtpSubmissionHelper.HandleTransientSmtpFailure(Exception e, InternalExchangeServer smtpServer, String recipientAddress)
   at Microsoft.Exchange.UM.UMCore.SmtpSubmissionHelper.SubmitMessage(MessageItem message, String senderAddress, String recipientAddress, OutboundConversionOptions submissionConversionOptions, String requestId)
   at Microsoft.Exchange.UM.UMCore.SmtpSubmitStage.InternalDoSynchronousWork()
   at System.Runtime.Remoting.Messaging.StackBuilderSink._PrivateProcessMessage(IntPtr md, Object[] args, Object server, Int32 methodPtr, Boolean fExecuteInContext, Object[]& outArgs)
   at System.Runtime.Remoting.Messaging.StackBuilderSink.AsyncProcessMessage(IMessage msg, IMessageSink replySink)

Exception rethrown at [0]:
   at System.Runtime.Remoting.Proxies.RealProxy.EndInvokeHelper(Message reqMsg, Boolean bProxyCase)
   at System.Runtime.Remoting.Proxies.RemotingProxy.Invoke(Object NotUsed, MessageData& msgData)
   at Microsoft.Exchange.UM.UMCore.SynchronousPipelineStageBase.SynchronousWorkDelegate.EndInvoke(IAsyncResult result)
   at Microsoft.Exchange.UM.UMCore.SynchronousPipelineStageBase.EndSynchronousWork(IAsyncResult r)"

Event ID: 1446
Task Category: UMCore
Source: MSExchange Unified Messaging
Details:

The Unified Messaging server failed to process the message with header file "C:\Program Files\Microsoft\Exchange Server\V14\UnifiedMessaging\voicemail\dcee02de-a993-4078-bd9e-223172797769.txt" within "10" minutes. The UM server will continue to process and deliver the message, but the "MSExchangeUMAvailability: % of Messages Successfully Processed Over the Last Hour" performance counter will be decreased.

My current setup is
Exchange 2010 SP3 with the following roles installed on the server
•      Mailbox
•      Hub Transport
•      Client Access
•      Unified Access

I’ve checked the receive connectors and they all have exchange server set as authentication and I only have 36 root authoritie certificates on this server.

Many thanks in advance