Ex2010 - Long Running Powershell Query Fails

Hello All-

I am trying to pull some information for a bunch of mailboxes (~7000 mailboxes), and am running the following...

Get-Mailbox -ResultSize Unlimited | Select Name, Alias, ServerName, Database, CustomAttribute10, PrimarySMTPAddress | Export-Csv C:\temp\export.csv

The query runs for a minute or so and then eventually stops with the following..

Processing data from remote server failed with the following error message: The connection to the specified remote host
 was refused. Verify that the WS-Management service is running on the remote host and configured to listen for requests
 on the correct port and HTTP URL. For more information, see the about_Remote_Troubleshooting Help topic.
    + CategoryInfo          : OperationStopped: (System.Manageme...pressionSyncJob:PSInvokeExpressionSyncJob) [], PSRe
   motingTransportException
    + FullyQualifiedErrorId : JobFailure

Has anyone seen behavior like this??  I've poked around the the powershell vDirs and AppPools in IIS looking for timeout/performance related things that may be the cause to no avail.  Any help is appreciated!

Thanks!

roc