I connect my external 1 TB harddisk so the Hard Disk sentinel show it 2048 GB and in overview tab it show this message "The status of the hard disk is unknown.
The configuration does not provide further disk status information. However, "Disk" menu "Surface Test" function can examine the disk functionality, reveal and fix possible problems.

Please use the "Report" menu "Send test report to developer" option to help us determining if it is possible to detect and display more information.
Please visit the "Hardware" and "Support -> FAQ" sections on www.hdsentinel.com for details."
How to fix it.

its SMART module problem check firmware with MRT or Pc3000 replace bad module with donor good one.

_________________
Specialized in Physical Data Recovery

https://lifeguarddatarecovery.com