RUNAS account - Specified Cast is invalid.

Question

When I attempt to look at the properties of a RUNAS account for SQL Server alerting / monitoring which I recently updated to add a new sql server in the distributionl, I get the following error.
Eventually it will come up but the distribution list of servers is no longer populated.
Any ideas?  
Specified Cast is not valid.
Note:  The following information was gathered when the operation was attempted.  The information may appear cryptic but provides context for the error.  The application will continue to run.
System.InvalidCastException: Specified cast is not valid.
   at Microsoft.EnterpriseManagement.Monitoring.Internal.MonitoringObjectGenerated.get_Id()
   at Microsoft.EnterpriseManagement.Common.EnterpriseManagementObject.GetObjectWrappersPostProcessing[T](ReadOnlyCollection`1 resultSet, IEnterpriseManagementObjectCreatable`1 constructorHelper)
   at Microsoft.EnterpriseManagement.Common.EnterpriseManagementObject.CreateMultiple[T](IList`1 dataAccessResultSet, EnterpriseManagementGroup managementGroup, Dictionary`2& instanceById, ObjectQueryOptions queryOptions)
   at Microsoft.EnterpriseManagement.Common.EnterpriseManagementObject.CreateMultiple[T](IList`1 dataAccessResultSet, EnterpriseManagementGroup managementGroup, ObjectQueryOptions queryOptions)
   at Microsoft.EnterpriseManagement.SecurityConfigurationManagement.GetApprovedHealthServicesForDistribution[T](ISecuredData securedData)
   at Microsoft.EnterpriseManagement.Mom.Internal.UI.Common.SDKHelper.<>c__DisplayClass2b.<GetApprovedHealthServicesForDistribution>b__2a(Object sender, ConsoleJobEventArgs e)
   at Microsoft.EnterpriseManagement.Mom.Internal.UI.Console.ConsoleJobExceptionHandler.ExecuteJob(IComponent component, EventHandler`1 job, Object sender, ConsoleJobEventArgs args)
Thanks Lance

Answer 1

We encountered this problem today.  I've written a script that will remove a specified computer from all RunAs Account distribution lists, and thought it might help avoid the problem next time we decommission an agent that has accounts distributed
to it.
The script also flags any accounts where the distribution list could not be accessed.
param (
[parameter(mandatory=$true)]$TargetName,
[switch]$WhatIf
Import-Module -Name OperationsManager
Write-Host
$Accounts=0
Get-SCOMRunAsAccount |
$Acct=$_
try {
$Dist = Get-SCOMRunAsDistribution -RunAsAccount $Acct
catch {
Write-Host -f yellow $('WARNING: RunAsAccount "{0}" has a corrupt RunAs Distribution!' -f $Acct.Name)
if ($Dist.Security -eq 'MoreSecure')
$FoundTarget = $false
$Dist.SecureDistribution = @($Dist.SecureDistribution | %{ if ($_.DisplayName -eq $TargetName) { $foundTarget = $true } else { $_ } } )
if ($foundTarget)
$Accounts++
$Dist | Set-SCOMRunAsDistribution -RunAsAccount $Acct -WhatIf:$WhatIf -Verbose
Write-Host
if ($Accounts -gt 0)
if ($WhatIf)
Write-Host -ForegroundColor green $("$TargetName would be removed from {0} RunAsAccount secure distribution lists" -f $Accounts)
} else {
Write-Host -ForegroundColor green $("$TargetName removed from {0} RunAsAccount secure distribution lists" -f $Accounts)
} else {
Write-Host -ForegroundColor cyan "$TargetName was not found in any RunAsAccount secure distribution lists"
Cheers,
Paul.