I actually don´t know what exactly did you try, but here are my some steps to try:
Step 1
Check the USB cable connection for the drive - try with different one and reconnect it to see if that corrects the I/O problems.
Step 2
Update the WD device driver. Restart the computer after updating the device driver to see if it corrected the I/O error problems. Do you see your device in Disk Management?
Step 3
Run the Windows Chkdsk tool to see if the drive or storage device has bad sectors or media causing the I/O errors. To run Chkdsk, click the Start button, then type "Chkdsk X: /f /r where "X" is the drive letter of the WD My Passport.
Step 4
Download the WD tool Data Lifeguard Diagnostics from here: http://support.wdc.com/product/download.asp?groupid=810&lang=en and test your drive.
If you take out the hard disk of the My Passport, it'll void your warranty. Also, have in mind that you WD My Passport is hardware encrypted, so if you take it out of its enclosure, you won't be able to read it and extract your data.
If your device is new, you could consider RMA, you can check here: http://support.wdc.com/warranty/index.asp?wdc_lang=en
Please, come and share what happened with the tests.
Hope that I helped.
KY_WD