Troubleshooting Child Process Error

EO products may create one or more child processes at runtime. For example, Both EO.Pdf and EO.WebBrowser dynamically create child processes to run the native browser engine. The child process may fail for various reasons and you may receive one of the following errors:

  • Failed to start image manager
  • Child process not ready
  • Required system file does not exist
  • Child process exited unexpectedly

When this occurs, please check the following:

Ensure Sample Application Runs

Download the full installer from the download page and run the installer. Afterwards run "c:\Program Files (x86)\Essential Objects\EO.Total xxxx\TabbedBrowser.exe" (where xxxx is EO version number) directly from that folder. Check if it starts correctly. If it starts correctly, enter a Url in the address bar and see if the page loads correctly. If this step does not work correctly, it means there is a problem with your environment and please check the following:

  • Apply all Windows Update. EO products may not run correctly on some Windows versions unless Windows is update to date. So if you have not applied all Windows update, please apply all Windows update and try to run the sample again;
  • Temporarily Disable Antivirus/Security Software. There maybe third party antivirus/security software on the system that interferes with EO library. Try to temporarily disable them and run the sample application again. If that resolves the issue, then please consider explicitly whitelist EO child process in your antivirus/security software;
  • Run it under a Different User. Run the sample application under a different user or run it as administrator. If that works, then it is usually related to user permissions.

Enable EO Worker Process

If the TabbedBrowser.exe sample application runs but your application does not, then the issue can usually be resolved by enabling EO worker process.

Explicitly Whitelist EO Child Process

If the issue is caused by third party antivirus/security software, then you may need to explicitly whitelist EO child process in those softwares. When this is the case it is recommended that you:

  1. Call EO.Base.Runtime.InitWorkerProcessExecutable to create eowp.exe dynamically. This method allows you to customize the name and the location of the executable;
  2. Follow the security software's instruction to whitelist the exe file name you used in the above step;