Sometimes a failing external drive will suddenly appear as "RAW" in Disk Management (no file system). Running chkdsk on a RAW drive is useless—it will simply say "The type of the file system is RAW. CHKDSK is not available for RAW drives." In this case, do not run chkdsk ; use data recovery software first.
| Drive Type | Capacity | USB Version | Approx. Time ( chkdsk /r ) | | :--- | :--- | :--- | :--- | | USB 2.0 Flash Drive | 64 GB | 2.0 | 1.5 - 2 hours | | Portable 2.5" HDD (5400 RPM) | 1 TB | 3.0 | 3 - 5 hours | | Portable 2.5" HDD (5400 RPM) | 4 TB | 3.0 | 12 - 18 hours | | Desktop 3.5" HDD (7200 RPM) | 8 TB | 3.1 (Gen 2) | 20 - 30 hours | | SSD External | 1 TB | 3.2 (Gen 2) | 30 - 60 minutes | chkdsk external drive
chkdsk X: /scan This performs an online scan without making changes. Then to apply only the necessary fixes: Sometimes a failing external drive will suddenly appear
After a repair, especially with /f , chkdsk often creates large folders named FOUND.000 , FOUND.001 , etc., containing FILE0000.chk files. These are recovered file fragments. They are not automatically renamed to their original extensions. Recovering meaningful data from .chk files requires third-party tools or manual hex inspection. | Drive Type | Capacity | USB Version | Approx