License activation error - Bad signed black licenses list

We are seeing this when the tool is activating the license, is there a reason why this can happen or documentation on this error?

@Chrisksang,

Please send us your license file through a private message, and let us know the name and version of Aspose API. We will investigate your scenario in our environment, and share our findings with you.

@Chrisksang,

Thank you for sending Aspose license file. We are unable to replicate this error in our environment. Please create a small application project, which reproduces this error in your environment, and then send us a ZIP of this project. We will investigate and share our findings with you. Your response is awaited.

Thanks but actually this does not always happen. With the same code we have multiple threads running ‘jobs’.
However it seems sometimes this error occurs during activation.

What is the meaning of this error and is there a way to figure out how to fix this when it happens such as re-attempt activation?

For example, 5 threads run, one of them may get this error but not always. If we had some context or background about this then perhaps we can help figure out what could cause this error in our code.

Simply the threads read file contents with ASPOSE, we call the ‘Apply ASPOSE license’ code in the beginning of the method.

Thanks
Chris

@Chrisksang,

We have tested your scenario in the multi-threaded application, and could not replicate the said error in our environment. Please create a small application project, which reproduces this error in your environment, and then send us a ZIP of this project.

Besides this, we recommend our clients to apply license once in some common area of the application, e.g. application start event. When the license is applied to the application or process level, then you do not need to apply license again till the lifespan of the application. Though, it is not harmful to apply license multiple times in the code.

Thanks we are seeing this still and have it applied in multiple places to ensure it is not having issues in multiple threads as it seems it is. This error 'Bad signed black licenses list ’ is thrown in some of these instances but not always.

It is hard to get code snippet to reproduce. Mainly, we have many threads, perhaps 10-100 which will be ‘activating’ the license from main application. We already tried applying license once from main app, but threads sometimes failed and went into trial and is why we apply within threads now.

@Chrisksang,

If it is being difficult to replicate the same error, then please track the actual source code, call stack and share a ZIP of the license file. We will investigate your scenario in our environment, and share our findings with you.