Q: Is there any way to recover data from the undetected hard drive?

If you connect the external disk, do you see it in Disk Utility?

Hello Tom, Have you tried Chkdsk command? If not, then please go for it. It is the most recommended solution to repair and recover data from hard disk. Good Luck!!

Assuming you have a Bootcamp Windows installation on a Mac, and an external disk is not visible in Windows explorer, can you switch to OS X, connect your external disk to the Mac, and post the output of the following OS X Terminal commands

diskutil list

diskutil cs list

Hello Tom, go through this http://www.stellarinfo.com/support/kb/index.php/article/how-to-search-for-lost-o r-deleted-volumes-on-your-windo  article. It has well explained all the steps to search and recover lost volume data.