Please read these suggestions before posting a support question.
Following them will allow others to understand your problem better and provide a solution faster and with less additional questions.

1. This forum "Support - (fb2k)" is for issues with the main application itself and official (bundled) components.
Issues with 3rd party components go to "3rd Party Plugins - (fb2k)", where individual components usually have their own topic. If you don't know or you are not sure what component causes the problem, post it here and it will be moved by a moderator if necessary. See the appendix in this topic for how to determine if a crash is caused by a 3rd party component.

2. Use the Troubleshooter to check for known problematic components.
Use the Help > Online Troubleshooter feature from the main menu to determine if any of components that you have installed are known to cause problems. See also this sticky topic.

3. Make sure you are using the latest version.
Check the official site for foobar2000, author's website or forum thread for 3rd party components. If you do not want to use latest versions for some awkward reason, your report is probably useless and will be ignored.

4. Describe your problem exactly.
Write in detail what specifically you were trying to do, what you had expected and what happened instead. In case of a sudden crash, try to recall what you had been doing just before it occurred. Try to reproduce the problem and write the result.

5. Post a list of all your components.
There is a handy button in the top right corner of "Preferences > Components" which automatically puts it into the clipboard. Use [codebox‎][/codebox‎] tags around the list so that it doesn't make your post unnecessarily long.

6. If the application crashed, make sure to click [Send Report] in the "foobar2000 has crashed" dialog.
Important information about it will be sent to the developers for further analysis, see also crash.foobar2000.org. This way, you can also immediately get a message stating the cause and possibly a solution for your problem in some cases.
(If you are a developer and want to get collected crash log data about your component(s), contact the staff.)