Fast Data Masker - Error scrambling xls file

Products

• CA Test Data Manager (Data Finder / Grid Tools)

Issue/Introduction

Unable to scramble excel files [with extension XLS ] .
Getting error after starting the mask.
The error message is mentioned below:
Exception in thread "main" org.apache.poi.openxml4j.exceptions.OLE2NotOfficeXmlFileException: The supplied data appears to be in the OLE2 Format. You are calling the part of POI that deals with OOXML (Office Open XML) Documents. You need to call a different part of POI to process this data (eg HSSF instead of XSSF) 
at org.apache.poi.openxml4j.opc.internal.ZipHelper.verifyZipHeader(ZipHelper.java:184) 
at org.apache.poi.openxml4j.opc.internal.ZipHelper.openZipStream(ZipHelper.java:241) 
at org.apache.poi.openxml4j.opc.ZipPackage.(ZipPackage.java:98) 
at org.apache.poi.openxml4j.opc.OPCPackage.open(OPCPackage.java:324) 
at org.apache.poi.util.PackageHelper.open(PackageHelper.java:37) 
at org.apache.poi.xssf.usermodel.XSSFWorkbook.(XSSFWorkbook.java:291)
at com.grid_tools.products.datamasker.Datamasker.doExcelFileMasking(Datamasker.java:10693) 
at com.grid_tools.products.datamasker.Datamasker.main(Datamasker.java:6354)

Environment

Fast Data Masker, FDM versions before 4.10 version

Cause

This error comes up because XLS file extension is not supported by FDM for masking Prior to the 4.10 version
. The "excel file" type of connection in fast data masker supports only xlsx file extensions.

Resolution

This error comes up because XLS file extension is not supported by FDM for masking prior to 4.10 version of FDM as the XLS is a Binary format and not an XML format as the XLSX is.
The "excel file" type of connection in fast data masker supports only xlsx file extensions.
Save the XLS file as XLSX using MS-Excel and try the masking. 

Or upgrade FDM to the latest version 4.10.15 or newer

Additional Information

Difference Between XLS and XLSX File Formats | File Format Blog