Thanks for your posting and using Aspose.Cells for Java.
Please download and try the latest version Aspose.Cells
for Java v22.214.171.124 and see if it resolves your issue.
If your issue still occurs, please provide us your runnable sample project and source files to investigate this issue. We will look into it and update you asap.
I am not an Aspose employee just another user like yourelf. We had an issue with very slow opening Excel files which was due to the Excel Add Ins which had a cumulated over time.
Removing / disbling them solved the problem for us.
Thanks for your feedback and using Aspose.Cells for Java.
It is good to know that your issue is resolved with the latest version. We have closed this thread now. If you encounter any other issue, please feel free to post on our forums. We will be glad to help you further.