Hi,
In the event code provided by you there is an error in filename.
Here you are trying to append your project suite path along with a absolute path to your excel file. Hence there is an error
Set App = Sys.OleObject("Excel.Application")
FileName = ProjectSuite.Path + "C:\Users\GSS\Documents\TestComplete 12 Projects\Gayatri\LVGI_Engg_CAR_EAR_New\LVGI__Engg_DataSheet.xls"
log.Message("FileName")
Set WorkBook = App.Workbooks.Open(FileName)
For example if you have placed your testcomplete project suite in "D:\Test" folder then as per your code FileName will have
"D:\TestC:\Users\GSS\Documents\TestComplete12Projects\Gayatri\LVGI_Engg_CAR_EAR_NEW\LVGI_Engg_DataSheet.xls"
Hence you would get an error