Hi eileenehernberger,
1. Does the same external hard drive get detected on any other computer?
Try the following steps:
Step 1:
I would suggest you to try changing the external hard drive’s drive letter and check if it helps:
Change, add, or remove a drive letter
Step 2:
Schedule chkdsk /r for next restart following the steps mentioned below and check if it helps:
a. Open an elevated command prompt. To do this, click Start, click All Programs, click Accessories, right-click Command Prompt, and then click Run as administrator.
If you are prompted for an administrator password or for a confirmation, type the password, or click Allow.
b. Type the following command, and then press ENTER after each command:
e:
Note: Where e: is the drive letter associated with external hard drive. Replace it with the drive letter associated with external hard drive.
chkdsk /r
c. When prompted to dismount and schedule chkdsk on next restart, type "Y" (without quotes) and then press enter.
d. Restart the computer.
Disclaimer: While performing chkdsk on the hard drive if any bad sectors are found on the hard drive when chkdsk tries to repair that sector if any data available on that might be lost.
Hope this helps.