public void GenerateDocument()
        {
            //Select the state for which we will print out the data
            this.stateCode = "MA";
            // Create WordTemplate
            WordTemplate wt = new WordTemplate();
 
            // Open the template document
            string templatePath = @"..\..\WordTemplateFiles\MailMergeTemplate.docx";
            wt.Open(templatePath);
     
            // Get the datatable for any state by parsing that state's specific csv file
            DataTable RegionData = GetCustomerData(@"..\..\WordData\MailMergeDemoData"+this.stateCode+".CSV");
           
          
            // Set the DataTable as the source for the mailmerge.
            wt.SetMailMerge(RegionData);
            wt.Process();
      
            // Save the document
            string docName = String.Format("MailMerge-{0}", this.stateCode);
            wt.Save(@"..\..\WordOutputFiles\"+ docName+ "_output"+".docx");
        }

 Template:  MailMergeTemplate.docx

 Output:  MailMerge-MA_output.docx