Thanks for your posting and using Aspose.Cells.
We were able to observe the Excel behavior of renaming worksheets as you described. We have therefore logged an enhancement request for this issue in our database.
We will look into it and fix this issue. Once, the issue is resolved or we have some other update for you, we will let you know asap.
This issue has been logged as
- CELLSNET-43310 - Renaming of duplicate worksheet names when combining workbooks
Thanks for your using Aspose.Cells.
Please download and try the latest fix: Aspose.Cells for .NET v220.127.116.11 and let us know your feedback.