My 1TB passport drive gives I/O error on copying files

After formatting, my 1TB external HDD drive gives I/O error on copying files. The drive has been detected and shows 1TB in my computer window and able to access. I have run WD diagnosis, except SMART test others had failed. Please help me.

If all other test have failed and you keep getting errors is recommended to replace the unit.

How to get an RMA, (Return Merchandise Authorization) or replace a defective product under warranty