Powershell v2.0 - find start path and instance and starting an application - wmi

Question

I am trying to write a simple script that stops and then starts a process (Application).
I can stop it fine, but can't find a way to start it again.
The string to start the process should be: "c:\AppFolder\AppName.exe" instance1
my script is:
$appName = "AppName.exe"
$filter = "name like '%"+$appName+"%'"
$result = Get-WmiObject win32_process -Filter $filter
$processid = $result.ProcessId
$command = $result.CommandLine
stop-process $processid
start $command
If I run $result | select * I see that there is an item for CommandLine which is "C:\AppFolder\AppName.exe" instance1
But If I try and do:
$command = $result.CommandLine
stop-process $processid
start $command
I get start-process : This command cannot be executed due to the error: The system cannot find the file specified
But if I manually type into a powershell window start "c:\AppFolder\AppName.exe" instance1 the Application starts fine.
Am I missing something here?
(n.b. it was suggested to me in "powershell v2 - how to get process ID" that I could use
$processid = get-process appName | select -expand id to get the processid, but when I expanded this to get all the items (probably not the correct term?)
in the object I couldn't see an option for CommandLine or similar)
I found the following (but still doesn't work)
$command = Get-WmiObject win32_process -Filter $filter | select -expandproperty CommandLine
write-host $command
This writes "c:\AppFolder\AppName.exe" instance1
start-process $command
But this then results in the following error:
Start-Process : This command cannot be executed due to the error: The system cannot find the file specified
.
At line:11 char:14
+ start-process <<<< $command
+ CategoryInfo : InvalidOperation: (:) [Start-Process], InvalidOperationException
+ FullyQualifiedErrorId : InvalidOperationException,Microsoft.PowerShell.Commands.StartProcessCommand
However, running:
start-process "c:\AppFolder\AppName.exe" instance1
starts the application?

Answer 1

I think I've solved it!! (and it's quite simple really) After much googling. . .
Apparently the start-process cmdlet only accepts a file location.
In order to add an argument (in this case the instance name) I need to use the attribute -ArgumentList
So I need to get the CommandLine item, and split it up, then pass it back in two parts
e.g.
$result = Get-WmiObject win32_process -Filter $filter
$comLine = $result.CommandLine -split"( )"
$comm = $commLine[0]
$inst = $commLine[2]
start-process -FilePath $comm -ArgumentList $inst
And this works as I expected it to.