Recorder/DOMX failures on one Bot Runner in multi-user RDP environment

hi ​@Karissa M 

Make sure when installing the bot agent that it installed with all users not only one user 

​@ahmed belal pif Of course, the agent is installed correctly, once for all users - these bot runners have been in place for 2 years already and can still run all bots and processes, just the recorder steps are failing now on one of them.

🔴 Root Causes – In Order of Likelihood

1. 🖥️ Windows Session 0 Isolation / GPU Rendering Contention (Most Likely)

On Windows Server 2022 with RDS multi-session, each user session runs in its own isolated desktop session. However, GPU and GDI rendering resources are shared across sessions. Chrome's rendering pipeline (especially with hardware acceleration enabled) competes for GPU resources between sessions.

• Bot Runner 1 (likely the first session to connect) gets priority GPU resource allocation.
• Bot Runner 2 (second session) operates with degraded rendering performance, causing Chrome to take longer to render DOM elements.
• The AA DOMX engine polls for element readiness within a timeout window. If Chrome is slow to render due to GPU starvation, DOMX finds the element, initiates the action, but the DOM re-renders (flickers) before the action completes — causing the "element not found" error.

Fix:

• Disable Chrome Hardware Acceleration for Bot Runner 2's Chrome profile:
  • Chrome Settings → System → Uncheck "Use graphics acceleration when available"
  • Or via command line flag: --disable-gpu
  • Or via Group Policy/Registry for the BR2 user profile specifically.

2. ⚙️ Chrome Extension Conflict Between Sessions (High Likelihood)

The AA Chrome Extension (bboccnojhhoegfffpcllbeigipedjedf) communicates with the Bot Agent via a native messaging host and local WebSocket. In a multi-session RDS environment:

• Both sessions load the same extension ID but must maintain separate native messaging pipes.
• If the extension's native messaging host is not properly isolated per-session, Bot Runner 2's extension may intermittently communicate with Bot Runner 1's Bot Agent pipe, causing erratic DOMX behavior.
• The extension's user data directory must be completely separate per session — if Chrome profiles are shared or overlapping, this will cause exactly the flickering/re-evaluation behavior described.

Fix:

• Verify that each Bot Runner account has a completely separate Chrome User Data Directory:
  • C:\Users\BotRunner1\AppData\Local\Google\Chrome\User Data
  • C:\Users\BotRunner2\AppData\Local\Google\Chrome\User Data
• Ensure the AA Bot Agent is configured to launch Chrome with the correct user profile for each session.
• Check that the AA Chrome Extension is installed per-user (not system-wide), so each user session has its own extension instance.

3. 🧠 CPU/Memory Resource Starvation on Bot Runner 2's Session

In RDS multi-session environments, Windows Fair Share CPU Scheduling distributes CPU time across active sessions. However:

• If Bot Runner 1's session is more CPU-active, Bot Runner 2 may receive fewer CPU cycles.
• The AA DOMX engine is CPU-intensive during element scanning. Under CPU pressure, DOMX may:
  • Find the element (first scan).
  • Initiate the action.
  • Lose CPU time mid-action while the page re-renders.
  • Report element not found on the next scan cycle.

Fix:

• Check Task Manager → Users tab during bot execution to compare CPU/Memory usage per session.
• Consider setting CPU affinity or priority for Bot Runner 2's processes.
• If the machine is undersized for two concurrent bot sessions with browser automation, consider dedicated VMs per Bot Runner (AA's recommended architecture).

4. 🔌 Bot Agent Port Conflict / WebSocket Collision

The AA Bot Agent uses local ports for communication between the Bot Agent service and the Chrome extension. On a multi-session machine:

• Both Bot Agents must use different port ranges.
• If there is a port conflict, Bot Runner 2's extension may intermittently fail to communicate with its Bot Agent, causing the DOMX engine to re-poll and ultimately time out.

Fix:

• Check the Bot Agent configuration for both sessions to ensure they are using non-overlapping port assignments.
• Review %APPDATA%\AutomationAnywhere\BotAgent\ for each user's configuration files.

5. 🔐 Windows User Profile / Registry Isolation Issue

The DOMX engine reads certain configuration values from the Windows Registry (HKCU) and user profile. On RDS:

• If the two Bot Runner accounts share any roaming profile settings or have profile path conflicts, DOMX configuration may be inconsistent for Bot Runner 2.
• Verify both accounts have fully separate, local (non-roaming) Windows profiles.

​@devendeshpande Thank you for the detailed response!

I will start by saying I followed some advice in another recorder issues question of turning off page caching and ai features in chrome, which has made a big difference. Still seeing some issues but intermittently, not all the time like before. I think it’s worth trying to get some further improvement, so I went ahead with reviewing per your suggestions.

1. I have turned off GPU acceleration per your recommendation on both profiles - honestly this is probably the most actionable suggestion since toggling page caching helped so much.
2. Both runners have their own chrome user data. But how do I verify that the extension is configured to run per each user?
3. I will add to the list to compare later if still having issues.
4. As it is an RDS AA would not allow me to install the bot agent per user, I was forced to do a system-wide install (but its been working for 2 years). My bot agent folder is in the shared C:\Program Files\Automation Anywhere\Bot Agent and I don’t see any per-user files here to look at which port is used for each.
5. Yes, they have fully separate non-roaming WINDOWS profiles.