Powershell DirectoryService object error neither caught nor trapped

Question

This is part of my script:

Trap {Write-Output \'Authentication Error trapped\'}
Try {New-Object System.DirectoryServices.DirectoryEntry $strDistinguishedName,$st         


        

Answer 1

I've recently come up against the same error, trying to instantiate a DirectoryEntry object to RootDSE on a domain where there is no trust with the current domain. What I found is that calling a method on the resulting object allows the exception to be successfully trapped/caught.

So this doesn't work as might be expected:

try 
{
    $RDSE = [adsi]"LDAP://UntrustedService/RootDSE"
}
catch
{
    Write-Warning "Unable to connect to service"
}

But this does:

try 
{
    $RDSE=[adsi]"LDAP://UntrustedService/RootDSE"
    [void]$RDSE.ToString()
}
catch [System.Management.Automation.RuntimeException]
{
    Write-Warning "Unable to connect to service"
}
catch #Default
{
    Write-Warning "Some other error"
}