|Most likely, because this is a laptop, the D: partition is your restore partition, yes some laptops don't hide the restore partition and people just try to save stuff there. |
So, if you have saved anything there, I would move what ever you want off the D partition to your documents. Now go to your recycle bin, right click, properties, turn off the recycle on the D: drive.
Next Go to your disk management and right click on the D: partition, change the drive letter, and set it to blank.