# Count GDI Handles for all Processes and send Mail to me when exceeding 6000
# needed with ActFax for Windows Graphics Conversion Problems after March 2021 Updates
#
# v1.0 - 20.03.2021 - Initial Release

# Get Ressource DLL
$sig = @'
[DllImport("User32.dll")]
public static extern int GetGuiResources(IntPtr hProcess, int uiFlags);
'@
Add-Type -MemberDefinition $sig -name NativeMethods -namespace Win32

# Loop thru Processes
$processes = [System.Diagnostics.Process]::GetProcesses()
[int]$gdiHandleCount = 0
ForEach ($p in $processes)
{
    try{
        $gdiHandles = [Win32.NativeMethods]::GetGuiResources($p.Handle, 0)
#       Cout a Sum of GDI Handles over all Processes
        $gdiHandleCount += $gdiHandles
    }
    catch {
    }
}

# Check total Number of Handles. There are max 9999 Handles on a Windows Server, so it is a good
# idea to send an alert when reaching 6000
If ($gdiHandleCount -gt 6000) {
#   When total GDI Objects greater 6000 send Mail to me with Number of Handles
    Send-MailMessage -to "RECIPIENT@DOMAIN.COM" -from "SERVERNAME <SERVER@DOMAIN.COM>" -SmtpServer "SMTP.SERVER.NAME" -Subject "ALERT from FaxServer" -body $gdiHandleCount.ToString()
  }