Recently my old USB drive became unreadable in Windows and started to be seen as RAW. This indicates that Windows cannot determine the structure of the file system on the disk. The reasons why this partition is defined as RAW may be different: the disk may not be formatted, the partition table header may be erased / corrupted / missing, there can be damaged sectors or any other physical problems either with the drive or with its controller.
From the user point of view, this RAW drive is displayed in Windows Explorer, but its size is detected as 0 (zero). When trying to open or read the data from the RAW partition, different errors appear, e. g.:
As a rule, the easiest way to recover the drive is to delete the current RAW partition and rebuild it when formatting. However, the data will be obviously lost that may be absolutely unacceptable. Let’s try to run disk check using the standard utility CHKDSK:
chkdsk e: /f
The utility returned that CHKDSK can not be executed for RAW-formatted drives.
CHKDSK is not available for RAW drives.
To restore the original file system on the RAW drive without formatting, let’s use the free command prompt tool TestDisk.
- Download the archive, unpack it and run the testdisk_win.exe file in the No Log mode.
- Find the drive, which file system is identified as RAW and select Proceed
- Then select the type of the partition table on the drive. As a rule, it is automatically identified as Intel for MBR partitions or EFI GPT for the GPT table. However, in some cases you should select None
- To start analyzing the drive data structure, select Analyze and then Quick Search on the next screen
- TestDisk will display the list of the partitions it found. Using P key, you can display the list of files in a partition (Q lets you quit the view mode). If the partition has the P label (the partition is highlighted in green), the partition is recoverable. If there is the D label, it will be deleted. To change the label, use arrow keys (right/left) on your keyboard.
After you selected all the partitions you want to recover, press Enter and then click Write (you have to be attentive here in order not to overwrite the partition table with the things you don’t need). If you have to run a deeper analysis of the drive, select Deep Search.
- After that (you may need to restart your computer), the tool will recover the original structure of the partition table and the file system (as a rule, it is either NTFS or FAT32) on the RAW drive and you can get access to the files stored on it.