Ensure window focus before sending keys

Question

I'm using a VBScript to SendKeys to a Cisco Client because it prompts for a username and password. However, I am having problems getting the command prompt focused.

I added AppActivate before every SendKeys command, but normal computer usage often breaks the focus in the time between these commands.

How can I ensure the command prompt has focus before sending keys?

Dim host, username, password, pathToClient
host = "host"
username = "username"
password = "password"
pathToClient = "C:\Program Files {(}x86{)}\Cisco\Cisco AnyConnect Secure Mobility Client\vpncli.exe"

Set ws = WScript.CreateObject("WScript.Shell")
ws.run("TASKKILL.exe /F /IM vpnui.exe"), 0, false
ws.run("cmd.exe"), 2, false
WScript.Sleep 300
ws.AppActivate("Command Prompt")
ws.SendKeys """" & pathToClient & """ connect " & host & "~"
WScript.Sleep 1000
ws.AppActivate("Command Prompt")
ws.SendKeys(username & "~")
WScript.Sleep 50
ws.AppActivate("Command Prompt")
ws.SendKeys(password & "~")
ws.run("TASKKILL.exe /F /IM cmd.exe"), 0, false

Answer 1

I used AutoHotKey to solve my issue. Here's my code:

host := "my.host.domain"
username := "myUsername"
password := "myPassword"
pathToClient = "C:\...\vpncli.exe"

DetectHiddenWindows, on
Process, Close, vpnui.exe
run, cmd.exe,, Hide
Sleep 100
ControlSend,, %pathToClient% connect %host%{Enter}, ahk_exe cmd.exe
Sleep 1000
ControlSend,, %username%{Enter}, ahk_exe cmd.exe
Sleep 50
ControlSend,, %password%{Enter}, ahk_exe cmd.exe
;Process, Close, cmd.exe