Script works in ISE and not SOME powershell CLI

Question

$wshell = New-Object -ComObject Wscript.Shell
$wshell.Popup("********Please Select the SOURCE Directory********",0,"Directory Selecter 5000",0x1)

Function Get-Folder($initialDirectory)

{

    $foldername = New-Object System.Windows.Forms.FolderBrowserDialog
    $foldername.rootfolder = "MyComputer"

    if($foldername.ShowDialog() -eq "OK")
    {
        $folder += $foldername.SelectedPath
    }
    return $folder
}

$a = Get-Folder

$wshellb = New-Object -ComObject Wscript.Shell
$wshellb.Popup("********Please Select the DESTINATION Directory********",0,"Directory Selecter 5000",0x1)
Function Get-Folder($initialDirectory)

{

    $foldername = New-Object System.Windows.Forms.FolderBrowserDialog
    $foldername.rootfolder = "MyComputer"

    if($foldername.ShowDialog() -eq "OK")
    {
        $folder += $foldername.SelectedPath
    }
    return $folder
}

$b = Get-Folder


Set-Content -Path "C:\script\scripts\script data.txt" -Value "$a" -Force
Set-Content -Path "C:\script\scripts\script data2.txt" -Value "$b" -Force

So this script works in ISE and if I copy/paste it into a CLI and that's it. If I navigate to the folder in the powershell CLI and run it from there it gives me this error:

New-Object : Cannot find type [System.Windows.Forms.FolderBrowserDialog]: verify that the assembly containing this type is loaded. At C:\script\scripts\pathingworking.ps1:8 char:19 + $foldername = New-Object System.Windows.Forms.FolderBrowserDialog + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : InvalidType: (:) [New-Object], PSArgumentException + FullyQualifiedErrorId : TypeNotFound,Microsoft.PowerShell.Commands.NewObjectCommand

The property 'rootfolder' cannot be found on this object. Verify that the property exists and can be set. At C:\script\scripts\pathingworking.ps1:9 char:5 + $foldername.rootfolder = "MyComputer" + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : InvalidOperation: (:) [], RuntimeException + FullyQualifiedErrorId : PropertyNotFound

You cannot call a method on a null-valued expression. At C:\script\scripts\pathingworking.ps1:11 char:8 + if($foldername.ShowDialog() -eq "OK") + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : InvalidOperation: (:) [], RuntimeException + FullyQualifiedErrorId : InvokeMethodOnNull

This error comes back twice, once for each instance of the folder selection window that is supposed to pop up.

I have tried -STA from run dialogue, shortcuts, and even from the CLI and it always gives me that error. I have verified using [System.Threading.Thread]::CurrentThread.GetApartmentState() that the open instance of powershell is STA. I can open a powershell CLI and navigate to the folder where the script is, invoke the script, it will give me the error, then I can copy\paste it in the same exact CLI and it works without issue. I have also right-clicked the file in Explorer and selected "run with powershell" and it also gives me the error. I have elevated the CLI to see if that helped with no success.

I fear this is some small oversight and hopefully someone can give me a hand.

using v1.0 windows 10

Answer 1

@rerun: Thanks, that helped me with my issue too (see Add-type -AssemblyName "System.Web" to determine MIME-type with Powershell 7 works in ISE but not Powershell).

I ran the command in both powershell.exe and the ISE (powershell_ise.exe). In the former, there was no assembly called System.Web, but I did find it in the latter.

Searching in the meantime had already helped me to figure out that using assembly in Powershell 7 requires a full path to the .dll.

At first I used using assembly System.Web, but that didn't help. With @rerun's hint I found an entry C:\WINDOWS\Microsoft.Net\assembly\GAC_64\System.Web\v4.0_4.0.0.0__b03f5f7f11d50a3a\System.Web.dll

I used this one at the beginning of the script like this using assembly "C:\WINDOWS\Microsoft.Net\assembly\GAC_64\System.Web\v4.0_4.0.0.0__b03f5f7f11d50a3a\System.Web.dll and that finally did the job.

Thanks :)

---

The functioning code looks like this:

using assembly "C:\WINDOWS\Microsoft.Net\assembly\GAC_64\System.Web\v4.0_4.0.0.0__b03f5f7f11d50a3a\System.Web.dll"

$FilePath = "C:\users\Daniel\Desktop\test.pdf"

$DocExtension = [System.IO.Path]::GetExtension($FilePath)
$DocMimeType  = [System.Web.MimeMapping]::GetMimeMapping($DocExtension)

Write-Output "Extension: $DocExtension `nMIME-type: $DocMimeType"

Answer 2

rerun's answer solves the errors, but doesn't do a whole lot of explaining. Designing a script in the ISE (which is what I do almost exclusively) is convenient because it will automatically load types and modules for you. If you plan on running the script from another CLI (Command Line Interpreter) you should make it a habit of explicitly loading needed modules and assemblies early on in the script, so that when those things are called upon later PowerShell will know what you're asking for.

Unfortunately there's no easy way to tell what you will need to do that for when it comes to what types are going to be inherently available, but a little trial and error usually points it out rather quickly, or if you look at your script and see that you are making a new object with System.Kitchen.Pasta, then you probably need to load the assembly for System.Kitchen first, so that it has the Pasta type available when you want it, so you could just include a call to load that assembly near the top of the script with no harm done.

In your specific case, as has already been pointed out, you will need to load the assembly that contains the FolderBrowserDialog box that you want to display. Adding the following as the first line of your script will resolve the errors that you are seeing:

Add-Type -AssemblyName "System.Windows.Forms"

Answer 3

Cannot find type [System.Windows.Forms.FolderBrowserDialog] is due to the assembly not being loaded.

load the assembly with

Add-Type -AssemblyName "System.Windows.Forms"