New-PublicFolderMigration Request Error

Hi,

I am trying to run the below command but with the following error:

New-PublicFolderMigrationRequest -SourceDatabase (Get-PublicFolderDatabase -Server HO-EX2010-PF) -CSVData (Get-Content C:\PFMigration\PFMailboxMap.csv -Encoding Byte)

However I am getting the following error:

Object Reference not set to an instance of the object

I can see this in event viewer but it doesn't seem to give much detail, anyone else seen this?

(PID 2280, Thread 11) Task New-PublicFolderMigrationRequest throwing unhandled exception: System.NullReferenceException: Object reference not set to an instance of an object.
   at Microsoft.Exchange.Management.RecipientTasks.NewRequest`1.AutoSelectRequestQueueForPFRequest(OrganizationId orgId)
   at Microsoft.Exchange.Management.RecipientTasks.NewPublicFolderMigrationRequest.InternalValidate()
   at Microsoft.Exchange.Configuration.Tasks.Task.<ProcessRecord>b__b()
   at Microsoft.Exchange.Configuration.Tasks.Task.InvokeRetryableFunc(String funcName, Action func, Boolean terminatePipelineIfFailed).

Many Thanks

Jason