Hi,

I am trying to move a mailboxes from our on prem exchange server to the cloud.  I am receiving the following error.

Error:
Deserialization fails due to one SerializationException: System.Runtime.Serialization.SerializationException: Unable to find assembly 'Microsoft.Exchange.MailboxReplicationService.Common, Version=15.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'.
   at System.Runtime.Serialization.Formatters.Binary.BinaryAssemblyInfo.GetAssembly()
   at System.Runtime.Serialization.Formatters.Binary.ObjectReader.GetType(BinaryAssemblyInfo assemblyInfo, String name)
   at System.Runtime.Serialization.Formatters.Binary.ObjectMap..ctor(String objectName, String[] memberNames, BinaryTypeEnum[] binaryTypeEnumA, Object[] typeInformationA, Int32[] memberAssemIds, ObjectReader objectReader, Int32 objectId, BinaryAssemblyInfo assemblyInfo, SizedArray assemIdToAssemblyTable)
   at System.Runtime.Serialization.Formatters.Binary.__BinaryParser.ReadObjectWithMapTyped(BinaryObjectWithMapTyped record)
   at System.Runtime.Serialization.Formatters.Binary.__BinaryParser.Run()
   at System.Runtime.Serialization.Formatters.Binary.ObjectReader.Deserialize(HeaderHandler handler, __BinaryParser serParser, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage)
   at System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream serializationStream, HeaderHandler handler, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage)
   at System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream serializationStream, HeaderHandler handler, Boolean fCheck, IMethodCallMessage methodCallMessage)
   at Microsoft.Exchange.Data.SerializationTypeConverter.<>c__DisplayClass3.<DeserializeObject>b__0()

Unable to find assembly 'Microsoft.Exchange.MailboxReplicationService.Common, Version=15.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'.

Exchange Management Shell command attempted:
'd8a1ebbf-10dd-4ac7-a0bf-98bb5322de5e' | New-MoveRequest -Remote -RemoteHostName 'HYBRID.ENDEMOLUK.COM' -RemoteCredential 'System.Management.Automation.PSCredential' -TargetDeliveryDomain 'Endemoluk.mail.onmicrosoft.com'

Elapsed Time: 00:00:01

This is affecting two on prem exchange servers and it was previously working.

Thanks.

You should update Exchange to resolve this error, but truth be told I haven't seen it before: http://support.microsoft.com/kb/2988229

Also, I would like to see the steps you have followed during the migration of mailboxes.

Meanwhile, you can refer to this informative technet library that covers all the required aspects for a successful migration between on prem exchange server and the cloud : https://technet.microsoft.com/en-us/library/jj906432%28v=exchg.150%29.aspx

Moreover, if you still unable to achieve this goal, I would suggest you to have a look on this automated solution (http://www.exchangemailboxmigration.com/) that could be a better approach to accomplish this task in more easier way without having any interruption.