title: VBA code query for automatic populating a cell based on another column's cell value
body: <p>I am working on a worksheet which has records of customers and their vehicles. In the vehicle details, I have column F which says its Petrol car, Column G which says it is Diesel car. Now i have already put data validation on these two columns to display Y and N. Thus the customers can select either Y or N. I want to write a VBA code for, if the customer selects Y in Column F (Petrol car) then Column G (Diesel Car) should automatically take value N for that customer. If the customer enters Y for Column G then Column F should automatically become N. </p>
  
  <p>Similarly, column H stands for Petrocard and column I stands for Smartfleet. Like above at a time only either of them will take value Y and other will take value N. Here also i have done data validation to give a drop down list of Y and N</p>
  
  <p>Similarly, column J stands for Two wheeler and column K stands for Any other vehicle. Like above at a time only either of them will take value Y and other will take value N. Here also i have done data validation to give a drop down list of Y and N.</p>
  
  <p>In addition to this in this worksheet I have already used a VBA code for another column C (Mobile number) to NOT allow duplicate entries in the excel sheet.</p>
  
  <p>This whole exact process is repeated from Column M to R and from Column T to Y.</p>