• Introduction
• Quick links
• 1. Crashes - Collecting the Minidump File when C4D Bug Report is Available
• 2. Crashes, Errors, Freezes - Collecting the Minidump File if C4D  Error Report Window is not Available
• 3. Reporting Rendering Problems (Possible Bugs, Incorrect Rendering, Problems with Lights, Materials, etc.)
• 4. Reporting Exceptionally Slow Rendering
• 5. Reporting Problems with Team Render

Introduction

If you run into a problem and can’t solve it on your own, the best step is to contact our support team. A clear and well-prepared bug report helps us quickly understand what’s happening and speeds up finding a solution.

On the other hand, a vague or messy description makes it harder for us to figure out the issue and usually slows down the whole process.

To make sure your report is as helpful as possible, here are some simple guidelines on how to write it properly:

Include as Much Information as Possible

1. The main problem

• Describe the issue in a single sentence.

• Focus only on this one issue—do not include other problems, even if they seem related. Submit one report per problem.

Good example: “Cinema 4D crashes when creating a Corona Light object.”
Bad example: “My Cinema 4D crashes and I don’t know why... maybe it’s related to the other bug I reported on the forum! Please help!”

2. What you did before the problem appeared

• Briefly explain the steps you took right before the issue happened, and describe what happened afterwards.

Good example: “I selected my active camera, then created a new Corona Light object, then enabled the ‘visible in reflections’ option. When I tried to render, Cinema 4D crashed with the attached error message.”
Bad example: “Help! My computer freezes!”

3. Minidump file (for crashes or freezes)

• If Cinema 4D crashes or freezes, please attach a minidump file.

• Instructions on how to find this file are provided in points 1 and 2 below.

4. Screenshots

• Attach screenshots of anything that may help us understand the problem, such as:

  • Render settings you changed

  • Material editor setups (especially if using plugins or non-standard materials)

  • The “Stats” panel in the Corona VFB (useful for slow rendering or pre-rendering issues)

• Any additional screenshots are welcome—the more context, the better.

5. Problematic scene

• When possible, attach the scene where the issue occurs.

• Our support ticket form allows you to upload large files.

• If you cannot attach files right away, submit your report without them—our team will guide you through sending them later.

6. Video of the issue (optional but very helpful)

• A short video showing the steps that lead to the problem is extremely valuable.

• If we can reproduce the bug on our side, the chances of fixing it are much higher.

• Free tools for screen recording include OBS Studio and ShareX.

• We understand recording may take extra time, so only do this if it’s convenient for you.

Other Guidelines

1. Use clear, short sentences

• Write your report in simple, easy-to-understand steps (1, 2, 3...).

• Avoid long or complicated descriptions, as they are harder to follow.

2. Report the issue in one place only

• Please choose either the support portal or the forum, but not both.

• Submitting the same issue in multiple places creates confusion and slows down the process.

• The best approach is to report the issue once and wait for our reply.

3. Always include version information

• Tell us which version of Corona and Cinema 4D you are using.

• This information is essential for us to reproduce and resolve the issue.

Quick Links

1. Chaos Help Center
https://support.chaos.com/hc/en-us/requests/new

• Use the support portal to submit a ticket for bugs, technical issues, rendering problems, licensing questions, or payment issues.

• Your report will be logged in our system, and one of our support agents will contact you as soon as possible.

2. Bug Reporting Forum
https://forum.corona-renderer.com/index.php?board=36.0 

• You can also report bugs in our forum.

• Support agents, developers, or community members may see your post and provide help.

• However, this method does not guarantee that your issue will be fully reviewed by the support team, and there is a chance it could be overlooked.

• For serious bugs or urgent issues, the support portal is always the recommended option.

1. Crashes - Collecting the Minidump File (When the C4D Bug Report is Available)

If Cinema 4D crashes, please describe exactly what you were doing right before it happened (for example, which button you clicked, what key you pressed, or what error message appeared). Along with this description, include the minidump file (.dmp).

What is a minidump file?

• A minidump file contains detailed information about what happened during a Cinema 4D crash or freeze.

• It allows our developers to better understand the issue and either provide a fix or explain the cause as quickly as possible.

How to get the C4D minidump file?

When C4D crashes, it usually displays "C4D Bug Report" window. To find the location of your minidump file:

1. Do not close the error report window just yet

2. Take note of the location mentioned as this is also where the minidump can be found

3. Go to that location and find the .dmp file.

4. Before sending, compress your minidump files into a single archive (formats such as .zip, .rar, or .7z are all acceptable). Archiving can reduce the file size by up to 10 times, which makes uploading and downloading much faster and easier.

5. Attach the archived minidump files together with your problem description using the support ticket submission form. If you cannot attach the files for any reason, simply submit your message without them. Our support team will then guide you on how to send the files later.

6. Always include version information

• Tell us which version of Corona and Cinema 4D you are using.

• This information is essential for us to reproduce and resolve the issue.

For macOS users:

Please note that minidump files are not generated for macOS. Instead, you can send us the bug report that is generated at the time of the crash. To obtain this file, open Cinema 4D, go to the C4D preferences,  and click the ''Preferences Folder'' tab at the bottom to open up a new window. Within this window you will find the ''_bugreports''.

If you are experiencing an issue when installing Corona, please send us the install log which is located here: /var/log/install.log

(Note that this path is not visible on macOS by default - the easiest way for you to get to that file is to open Finder, then Go -> Go To Folder... and write "/var/log" in there.) .

Always include version information

• Tell us which version of Corona and Cinema 4D you are using.

• This information is essential for us to reproduce and resolve the issue.

2. Crashes, Errors, Freezes - Collecting the Minidump File if C4D  Error Report Window is not Available

If you are experiencing a recurrent error that you are able to reproduce (for example a window shows up in Cinema 4D saying "DEBUG ALERT" or it freezes in certain situation):

1. Simply download and use this tiny application to obtain the minidump file:

Process Explorer

2. When the error message appears, or during the freeze, run Process Explorer, find "Cinema4d.exe" process, right-click it, and go to Create Dump > Create Minidump..., then save the file in a desired location. 

3. Archive the file using software of your choice (.zip, .rar, .7z will work fine) - this way the dump file may get even 10 time smaller! 

4. Attach the archived minidump files together with your problem description using the support ticket submission form. If you cannot attach the files for any reason, simply submit your message without them. Our support team will then guide you on how to send the files later.

Always include version information

• Tell us which version of Corona and 3ds Max you are using.

• This information is essential for us to reproduce and resolve the issue.

3. Rendering Problems (Possible Bugs, Incorrect Rendering, Problems with Lights, Materials, etc.)

Save Project with Assets option in C4D:

When submitting your support ticket, attach your problematic scene. 
We provide an option to attach large files in our support ticket submission form. If you do not have any files that you could attach, or if you think something isn't working right, please skip this step and send us your message without any files. Our support team will ask you for files later and will explain how to attach them. 

4. Exceptionally Slow Rendering

5. Reporting Problems with Team Render