WD 4TB external hard drive losing data?

WD 4TB external hard drive losing data? Thankfully, I have other WD external drives to back data up–I use the 4TB as a “stockpile” containing data from other drives. Lately, the 4TB has lost data I previously copied to it. Am I missing something? (Lenovo P50 Win 7 Pro 64bit, I7, 750 gb SSD, 12 gb RAM)

You can try to test your hard drive from the diagnostic software like Windows Data lifeguard diagnostics or WD Drive utilities to rule out the issue with the drive itself.

You can click on the below mentioned links to download the above mentioned software.