Using WIA to do OCR, why load image is null

Question

I want to use PowerShell and Programs that come with windows 7 to do OCR, in this code, I miss a wrong, objImage is null, I can`t know why

$imagePath = "F:\image.png"  
Test-Path -Path "F:\image.png"  
Start-Service -Name "stisvc"

$objOCR = New-Object -ComObject Wia.ImageFile 
$objImage = $objOCR.LoadFile($imagePath)  
if ($objImage -ne $null) {      
    $ocrResult = $objImage.OCR()      
    if ($ocrResult.Text -ne $null) {         
        Write-Host "Result:"         
        Write-Host $ocrResult.Text     
    }     
    else {         
        Write-Host "OCR Wasted。"     
    } 
} 
else {     
    Write-Host "Can not load Image" 
}

check path is true

I try to start WIA in Line 3, and check path, and Check WIA's dependencies，I expect to solve this question or find a new way to do OCR by using no rely on third-party libraries