HP Laptops - Display Going Black on XA Login Screen (Conextant Flow.exe)

HP Laptops - Display Going Black on XA Login Screen (Conextant Flow.exe)

CONFIGURATION

• XA LOCKING Kiosk Mode (XA 4.10.x, 4.11.x, 4.12.x)
• HP Devices
  • HP EliteBook 850 G5 & HP EliteBook 840 G5
  • Other HP devices

PROBLEM BEHAVIOR

After rebooting a system, the XA login is presented and then the screen goes black.

The mouse pointer is still visible, and the system will respond to badge taps (or you can log in 'blind' by entering your UID <tab> Password <enter>). After successful authentication, the Windows desktop appears and functions as normal.

ROOT CAUSE: Conextant Flow.exe

This behavior is a known interaction with the Conexant drivers on some HP systems. There is a specific executable, flow.exe, that is the culprit.

flow.exe is starting up after the XA Privacy Shield is executed, and it steals focus and effectively breaks the placement of the login box.

The default behavior of this program is a 30 second delay and that is long enough that it interferes with our executable. 

NOTE: In most cases of this, an Alt+tab is another way to bring it back in addition to what you already see.

RESOLUTION 1 (recommended) - Configure the flow.exe to execute before the Privacy Shield runs

1. Configure flow.exe to execute before our Privacy Shield executes.
2. This method itself has several ways to implement and we have found that a Group Policy to create a scheduled task has been the most effective:
   [Computer Configuration\Preferences\Control Panel Settings\Scheduled Tasks]
   Run at user logon Enabled: Yes
   Program/script: "C:\Program Files\conexant\flow\sacpl.exe"
   Arguments: /sa3 /uid:FLOW /delay:5
   Start in: C:\Program Files\Conexant\FLOW
   Settings:
   Stop if the computer ceases to be idle: No
   Restart if the idle state resumes: No
   Start the task only if the computer is on AC power: No
   Stop if the computer switches to battery power: No
   Allow task to be run on demand: Yes
   Stop task if it runs longer than: Immediately
   If the running task does not end when requested, force it to stop: Yes
   If the task is already running, then the following rule applies: IgnoreNew

RESOLUTION 2 - Remove flow.exe from the disk

1. Some customers have just deleted flow.exe from the disk.
   • It is a non-essential part of the driver package, and they did not see any negative side effects from just removing the executable and using the machine without it.

RESOLUTION 3 - Delay Launch of XA

Another way to prevent the behavior is to delay XA from launching so that it displays our login dialog after the Conextant Flow application has started:

This method involves removing two entries from the Windows\Run key in the registry and replacing them with a batch file:

1. Remove these two values from the registry:
   [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
   "hciNetStatus.exe"=""C:\\Program Files (x86)\HealthCast\eXactACCESS\hciNetStatus.exe" hcikmlock"
   "xahid_kiosk.exe"="C:\\Program Files (x86)\HealthCast\eXactACCESS\xahid_kiosk.exe"
2. Add this value as a string:
   [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
   "Launch_XA"=""C:\Program Files (x86)\HealthCast\eXactACCESS\Launch_XA"
3. Create a new batch file in the ExactAccess directory and place these commands in it. The batch file is simple and has a 45-second waiting period before engaging the Privacy Shield. Give this a try to test and see if it will be enough to prevent flow.exe from breaking the login box.:
   • @echo off
   • timeout 45
   • start "" "C:\Program Files (x86)\HealthCast\eXactACCESS\xahid_kiosk.exe"
   • start "" "C:\Program Files (x86)\HealthCast\eXactACCESS\hciNetStatus.exe" hcikmlock
4. There is a risk with this method - there is no built-in way to prevent Windows from displaying the command prompt window and having it on-screen would make it possible for a user to close it and that would stop XA from launching altogether.