Why does my Screenshot Function not work as a Job - powershell

Question

I have a function inside a Job which takes a Screenshot. The Script itself gets executed by Taskscheduler as a domain admin. I also checked "Run with highest privileges".
The Job should do a Screenshot and then send an E-Mail, but both of those thing don't happen. I also don't see an error message (maybe because it's a background job?). Maybe the E-Mail doesn't get sent because it wants to attach the screenshot to the e-mail, but can't because the screenshot wasn't created.
Why does my function not Take the Screenshot? The domain admin has privileges to write to the destination. The screenshot gets created when I run the function outside the start-job. if i have the function inside start-job it doesn't get created, doesn't matter if the script is started via Taskscheduler or manually.
What am I missing?
The following Code starts the Job and takes the screenshot:
Start-Job -Name LogikWebserverWatch {
function Take-Screenshot([string]$outfile)
{
[int]$PrtScrnWidth = (gwmi Win32_VideoController).CurrentHorizontalResolution
[int]$PrtScrnHeight = (gwmi Win32_VideoController).CurrentVerticalResolution
$bounds = [Drawing.Rectangle]::FromLTRB(0, 0, $PrtScrnWidth, $PrtScrnHeight)
$bmp = New-Object Drawing.Bitmap $bounds.width, $bounds.height
$graphics = [Drawing.Graphics]::FromImage($bmp)
$graphics.CopyFromScreen($bounds.Location, [Drawing.Point]::Empty, $bounds.size)
$bmp.Save($outfile)
$graphics.Dispose()
$bmp.Dispose()
}
while ((Get-Process LogikWebserver).Responding) {sleep -Milliseconds 50}
if (!(Get-Process LogikWebserver).Responding) {
Try{
$utf8 = New-Object System.Text.utf8encoding
$datetime = (get-date).ToString('yyyyMMdd-HHmmss')
Take-Screenshot -outfile C:\Install\LogikWebserverErrorReporting\Screenshot-$datetime.png
# some more code [...]
} Catch { some more code [...] }
}}

Answer 1

The documentations says that:
A Windows PowerShell background job runs a command without interacting with the current session.
So you may have to load the required assemblies inside your job before it will work.
When I tried your code above, it only created a screenshot when run outside of a job (as you mentioned), however adding this line to the top of the Start-Job ScriptBlock caused it to work from inside the job as well:
[Reflection.Assembly]::LoadWithPartialName("System.Drawing")
Or, as the above is now depracated:
[System.Reflection.Assembly]::LoadFrom("C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.6.1\System.Drawing.dll")
Or
Add-Type "C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.6.1\System.Drawing.dll"
Note that I have not tested this when running from a schedued task.

Answer 2

dont use function . just write your function code in script block like this :
Start-Job -Name LogikWebserverWatch {
Add-Type -AssemblyName "System.Drawing"
[int]$PrtScrnWidth = (gwmi Win32_VideoController).CurrentHorizontalResolution
[int]$PrtScrnHeight = (gwmi Win32_VideoController).CurrentVerticalResolution
$bounds = [Drawing.Rectangle]::FromLTRB(0, 0, $PrtScrnWidth, $PrtScrnHeight)
$bmp = New-Object Drawing.Bitmap $bounds.width, $bounds.height
$graphics = [Drawing.Graphics]::FromImage($bmp)
$graphics.CopyFromScreen($bounds.Location, [Drawing.Point]::Empty, $bounds.size)
$bmp.Save($outfile)
$graphics.Dispose()
$bmp.Dispose()
}
while ((Get-Process LogikWebserver).Responding) {sleep -Milliseconds 50}
if (!(Get-Process LogikWebserver).Responding) {
Try{
$utf8 = New-Object System.Text.utf8encoding
$datetime = (get-date).ToString('yyyyMMdd-HHmmss')
Take-Screenshot -outfile C:\Install\LogikWebserverErrorReporting\Screenshot-$datetime.png
# some more code [...]
} Catch { some more code [...] }
}