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Your machine is not starting, behaving weird or crashing? We are sorry to hear that. This chapter tries to help you to help yourself. Please try to find the root of your problem. Maybe the solution will be obvious then. If not we will help you in the forum.

Please remember that this is a two step process: First, try to diagnose the problem and collect as much information as possible. Second, report the issue if you cannot find a solution yourself. If you skip the first step we will likely send you to this page.

Step 1: Diagnosing Your Issue

Do you already know how to turn on debugging and increase log verbosity?

What kind of issue are you having?

If you coils are not firing, switches are not working or hardware is behaving weirdly in general read our hardware troubleshooting guide.

Step 2: Prepare a Report and Ask in the Forum

Please include the following information if available and relevant:

Output of MPF diagnosis

If your game won't run, let's make sure MPF is ok. This will also tell use which MPF and MPF-MC version you are using. Run mpf diagnosis from within your machine folder to see if your installation is fine:

$ mpf diagnosis

MPF version: MPF v0.50.0-dev.11
MPF install location: /data/home/jan/cloud/flipper/src/mpf/mpf
Machine folder detected: /data/home/jan/cloud/flipper/src/good_vs_evil
MPF-MC version: MPF-MC v0.50.0-dev.5 (config_version=5, BCP v1.1, Requires MPF v0.50.0-dev.10)

Serial ports found:
    desc: Quad RS232-HS
    hwid: USB VID:PID=0403:6011 LOCATION=1-12
    desc: Quad RS232-HS
    hwid: USB VID:PID=0403:6011 LOCATION=1-12
    desc: Quad RS232-HS
    hwid: USB VID:PID=0403:6011 LOCATION=1-12
    desc: Quad RS232-HS
    hwid: USB VID:PID=0403:6011 LOCATION=1-12

Relevant Configuration

Please provide the relevant configuration snippets. Leave out anything which is not related. For instance if you got problems with lights on your P-Roc or FAST platform provide the configuration for the relevant lights, the p_roc or fast section and any light_players or shows which are used when the problem occurs.

Attach a Log with debug and verbose logging

Please attach the log with verbose logging from MPF or MPF-MC (depending where your problem occurred). Make sure you enabled debug on the relevant devices and/or platforms. See how to turn on debugging and increase log verbosity for details.

A link to your machine config also help. Ideally this would be some git repository which can be checked out and browsed online.

Prepare the Error Message

Your error message likely is inside your log. However, please include it inside your message as well. See Reading MPF Errors for how to read the error.

Please check the relevant device or platform documentation for any mentions of that error. Often we already documented how to solve it.

Tell Us How to Reproduce Your Problem

It might be hard for us to help you if we cannot reproduce your issue. Is there a way you can provide a minimal config which shows your problem? Try to remove everything unrelated to your problem and bring it to its bare minimum. Sometimes you will find the root of the issue while doing this. You would be surprised how often issues are caused by seemingly unrelated devices or configs.

Ideally you can provide a single file test which fails or shows your issue in its log. This allows us to verify the issue quickly and provide a quick fix. But don't worry if this not possible. Just a minimal machine config is also fine. In that case please tell us how to run your machine to experience the issue.

Ask In the Forum

With all this information, now you can ask in our a support forum. Please keep in mind that MPF is an open source project and we are doing this for fun in our spare time. Be kind and patient. If you provide more relevant information it is likely that somebody can help you. More is not always better if it is not relevant to your problem. But missing information will just delay the overall process.

  1. If you have a problem with a device (e.g. a ball_lock) or a platform (e.g. P-ROC or FAST) add debug: True to the relevant config section to enable extra debug output.
  2. Add a log of your game. Therefore, run your game with mpf both -v -V and grab the latest MPF and MC log from the log folder in your machine.
  3. Describe how to reproduce your problem.
  4. Provide relevant config snippets or, if possible, a link to download/checkout your machine config so we can reproduce the issue.

Consider Improving the Documentation

Did you solve your issue but found that some relevant information in the documentation is missing or should be linked/located elsewhere? Either tell us in the forum or consider improving the documentation yourself to save future users some troubles the same way others saved you some troubles by writing this documentation.

More How-tos

Something missing or wrong? You can fix it!

This website is edited by people like you! Is something wrong or missing? Is something out of date, or can you explain it better?

Please help us! You can fix it yourself and be an official "open source" contributor!

It's easy! See our Beginner's guide to editing the docs.

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