Unable to monitor Exchange Server 2007

Question

Hi,

I want to monitor exchange server 2007 using powershell scripts.  Here are the scripts which I have used for that.

$secpasswd = ConvertTo-SecureString "password" -AsPlainText -Force 
$mycreds = New-object -typename System.Management.Automation.PSCredential("domain\Admin",
$secpasswd)
Enter-pssession 192.168.1.153 –credential $mycreds

$server='client-pc-1.domain.com';$pwd= convertto-securestring 'password' -asplaintext -force;
$cred=new-object -typename System.Management.Automation.PSCredential -argumentlist 'Admin',
$pwd; invoke-command -computername $server -credential $cred -scriptblock {Add-PSSnapin 
Microsoft.Exchange.Management.PowerShell.Admin; Get-ExchangeServer}

But I have landed in the following Exception

Processing data from remote server failed with the following error message: The
 WSMan provider host process did not return a proper response.  A provider in the
 host process may have behaved improperly. For more information, see the 
about_Remote_Troubleshooting Help topic.
    + CategoryInfo          : OperationStopped: (System.Manageme...pressionSyncJob:
PSInvokeExpressionSyncJob) [], PSRemotingTransportException  + FullyQualifiedErrorId : JobFailure

Can anyone please help me to solve this?

Thanks
Sebastian