Powershell v2 script need some help

Question

I have a powershellv2 script for starting services but I can't get it to work propparly I know the start-service command only works localy but I can't seem to get the (gwmi win32_service -computer $comp -Filter "name='$serviceName'").StartService() command to work, I get the following error

You cannot call a method on a null-valued expression. At line:1 char:146 + (Get-WmiObject win32_service -computer cap-test4-biz1 -Credential captest\jola_adm -filter "Name='BTSSvc$BizTalkServerApplication'").invokemethod <<<< ("StartService",$null) + CategoryInfo : InvalidOperation: (invokemethod:String) [], RuntimeException + FullyQualifiedErrorId : InvokeMethodOnNull

i have pastet the script below, hopeing some one can help

 $computername = "remoteserver"
    $password = type H:\Powershell\MyPassword.txt | ConvertTo-SecureString
    $cred = New-Object -TypeName System.Management.Automation.PSCredential -argumentlist “domain\user”,$password


    function StartIfStopped([string]$ServiceName) {
        $Service = Get-WmiObject Win32_Service -computername $computername -cred $cred -Filter "name='$ServiceName'"
        if (!$Service) {
            # Service is not installed
            Write-Host "$ServiceName is not installed on this machine."
        } else {
            # Service is installed
            if ($Service.State -eq "Stopped") {
                if ($Service.StartMode -eq "Disabled") {
                    Write-Host "Cannot start service $ServiceName as it is disabled."
                } else {
                    Write-Host "Starting service $ServiceName ..."

                    Start-Service $ServiceName


                }           
            } else {
                Write-Host "$ServiceName is already running."
            }
        }
    }

    StartIfStopped 'BTSSvc$BizTalkServerApplication' 
    StartIfStopped 'BTSSvc$TASMSMQHost'
    StartIfStopped 'BTSSvc$TASProcessingHost'
    StartIfStopped 'BTSSvc$TASSendHost'
    StartIfStopped 'BTSSvc$TASTrackingHost'

Answer 1

I think it's the conversion of your password to a SecureString that's doing it. I was able to get your script to work by changing line 2 to this:

$password = type H:\Powershell\MyPassword.txt | ConvertTo-SecureString -AsPlainText -Force

By default ConvertTo-SecureString takes an encrypted string as its input. -AsPlainText tells it to use a plain text string.

Then there's the idea that you're storing a password in a text file....

Answer 2

$computername = Get-Content H:\computers\Computers.txt;
$password = type H:\Powershell\MyPassword.txt | ConvertTo-SecureString
$cred = New-Object -TypeName System.Management.Automation.PSCredential -argumentlist “domain\user”,$password
$filename = "{0:yyyy-MM-dd} start" -f (Get-Date) 
$tid = Get-Date -f HH:mm:ss



function StartIfStopped([string]$ServiceName) {
    $Service = Get-WmiObject Win32_Service -computername $computername -cred $cred -Filter "name='$ServiceName'"
    if (!$Service) {
        # Service is not installed
        Write-Host "$ServiceName is not installed on $computername."
    } else {
        # Service is installed
        if ($Service.State -eq "Stopped") {
            if ($Service.StartMode -eq "Disabled") {
                Write-Host "Cannot start service $ServiceName as it is disabled." 
            } else {
                #Write-Host "Starting service $ServiceName ..." 
                Write-Output "$tid Starting $ServiceName ." >> H:\logfiler\$filename.txt

                #virker kun lokalt på servere       
                #Start-Service $ServiceName

                #virker på remote servere også i andre domainer 
                (Get-WmiObject Win32_Service -filter "name='$ServiceName'" -computername $computername -cred $cred ).StartService()

            }           
        }  else {
            #Write-Host "$ServiceName is already running."
            Write-Output "$tid already running $ServiceName." >> H:\logfiler\$filename.txt
        }
    }
}

StartIfStopped 'BTSSvc$BizTalkServerApplication'
StartIfStopped 'BTSSvc$TASMSMQHost'
StartIfStopped 'BTSSvc$TASProcessingHost'
StartIfStopped 'BTSSvc$TASSendHost'
StartIfStopped 'BTSSvc$TASTrackingHost'
StartIfStopped 'BRNTService'
StartIfStopped 'TimerService'
StartIfStopped 'BouncedMailTracker'
StartIfStopped 'CMToolService'
StartIfStopped 'CalculationExcelService'
StartIfStopped 'ControlNTService'
StartIfStopped 'EnvelopeService'
StartIfStopped 'PrinterService'

Update on the script, i got it working but now i need it to log-on multiple servers and start the services.

Answer 3

I know this question is 6 years old by now but anyway.

Looking at the error message. The problem is the $ in BTSSvc$BizTalkServerApplication and all the other service names with a $. It has to be escaped like so:

Get-WmiObject -ClassName Win32_Service -Filter "Name='BTSSvc`$BizTalkServerApplication'"