External drive not showed up on Disk Utilities! Help

Hello,

I have an external drive that is no longer recognized by my iMac Mid2011. I updated to mac OS High Sierra. Checked time machine and it said, "Latest Back Up January, 17, 2018. I tried the instruction on the WD website for “My Book Drive Not Recognized” by power off computer, disconnect… Also tried leaving it off for a couple hours. So far nothing changes. The unit has steady flashing light every 2 seconds.

Any suggestions? Thank you very much.

Hi fishbyfish,

Maybe you should have a look at this KBA:
https://support.wdc.com/knowledgebase/answer.aspx?ID=20502&s=

Thank you very much for the aritcle. I have a question before attempting to convert to APFS format. By partitioning the drive, will the data be safe? Mostly they are my photos. The time machine is also backing up my computer to this drive.