Currently, Aspose.Cells can only preserve macros during the conversion of Excel files and supports to delete them as well. However, it does not support to create, inject, modify, extract/ validate or execute macros or vba codes at the moment.
We only plan to create, manipulate or embed VB codes/macros before the end of Q1, 2015, the ticket id is “CELLSNET-40353”. However, we cannot support to execute them.
If you need to assign and validate Digital Signatures, you may use the Aspose.Cells APIs for the task, see the document for your reference: