Error When Testing on iOS Simulator: Couldn’t Register with the Bootstrap Server

28 February 2025 Stephan Petzl Leave a comment Xcode

Encountering errors while testing on the iOS Simulator can be frustrating, especially when the error message is cryptic and doesn’t offer an immediate solution. One such error is:

Couldn’t register com.myApp.debug with the bootstrap server. Error: unknown error code.

This error typically indicates that another instance of the process is already running or is hung in the debugger, resulting in the app being unable to register with the bootstrap server. Below, we provide a comprehensive guide to resolving this issue.

Understanding the Problem

The problem arises when the iOS Simulator or device fails to register your app due to an existing instance not being correctly terminated. This often results in a process known as a ‘zombie’ process, where the app is still registered with the system but is no longer active.

Potential Solutions

• Restart the Simulator: This is the simplest approach. Quitting and restarting the simulator can often resolve the issue.
• Reset the Simulator: If restarting doesn’t help, try resetting the simulator. To do this:
  1. Go to the “iOS Simulator” menu.
  2. Select “Reset Content and Settings…”.
  3. Confirm the reset when prompted.
• Check for Zombie Processes: Use the terminal to identify any zombie processes. Run:

  ps -el | grep 'Z'

  If you find your app listed, a reboot might be necessary to clear these processes.

• Kill Zombie Processes: For a more technical solution, use the following command in the terminal to remove any hanging processes:

  launchctl list|grep UIKitApplication|awk '{print $3}'|xargs launchctl remove

• Reboot Your System: If the above steps fail, a full system reboot can ensure that all processes are properly reset.

Preventive Measures

To minimize the occurrence of this error, ensure that you properly stop the app using the “Stop” button in Xcode before rerunning it. Additionally, avoid switching between different simulators frequently, as this can trigger the issue.

Using Repeato for Test Automation

For developers looking to streamline their testing process, Repeato offers a robust solution. As a no-code test automation tool, Repeato allows you to create, run, and maintain automated tests for iOS, Android, and web apps efficiently. Its use of computer vision and AI enhances test accuracy, while features like data-driven and keyword-driven testing offer flexibility.

By automating your testing with Repeato, you can avoid many manual testing pitfalls, such as the aforementioned bootstrap server registration issue. Its fast test recording and execution capabilities, combined with support for command line scripts and JavaScript code for complex tasks, make it an excellent alternative to tools like Katalon. Furthermore, all tests and workspace data are stored in text and JSON format, facilitating easy version control.

Explore how Repeato can enhance your testing workflow by visiting our documentation page for more detailed insights.

Check it out!

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