How to determine if a drive is external storage

How can I tell if the drive is an external USB storage device? I checked DriveInfo.DriveType but with my 1TB external hard drive connected via USB it shows up as a fixed drive.



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2 answers

Based on the comment from Floyd Pink I used the link. This allows me to determine if the device is external or not.

public bool IsProjectOnExternalDisk(string driveLetter)
        bool retVal = false;
        driveLetter = driveLetter.TrimEnd('\\');

        // browse all USB WMI physical disks
        foreach (ManagementObject drive in new ManagementObjectSearcher("select DeviceID, MediaType,InterfaceType from Win32_DiskDrive").Get())
            // associate physical disks with partitions
            ManagementObjectCollection partitionCollection = new ManagementObjectSearcher(String.Format("associators of {{Win32_DiskDrive.DeviceID='{0}'}} " + "where AssocClass = Win32_DiskDriveToDiskPartition", drive["DeviceID"])).Get();

            foreach (ManagementObject partition in partitionCollection)
                if (partition != null)
                    // associate partitions with logical disks (drive letter volumes)
                    ManagementObjectCollection logicalCollection = new ManagementObjectSearcher(String.Format("associators of {{Win32_DiskPartition.DeviceID='{0}'}} " + "where AssocClass= Win32_LogicalDiskToPartition", partition["DeviceID"])).Get();

                    foreach (ManagementObject logical in logicalCollection)
                        if (logical != null)
                            // finally find the logical disk entry
                            ManagementObjectCollection.ManagementObjectEnumerator volumeEnumerator = new ManagementObjectSearcher(String.Format("select DeviceID from Win32_LogicalDisk " + "where Name='{0}'", logical["Name"])).Get().GetEnumerator();


                            ManagementObject volume = (ManagementObject)volumeEnumerator.Current;

                            if (driveLetter.ToLowerInvariant().Equals(volume["DeviceID"].ToString().ToLowerInvariant()) &&
                                (drive["MediaType"].ToString().ToLowerInvariant().Contains("external") || drive["InterfaceType"].ToString().ToLowerInvariant().Contains("usb")))
                                retVal = true;

        return retVal;


Using WMI Select * from Win32_LogicalDisk

as in Royi Namir's answer and DriveInfo.DriveType

showing my external type as "Local Disk" which I cannot use to determine if the disk is external.



you can use WMI with

Select * from Win32_LogicalDisk

you have

 Select Case .DriveType
        Case 0
          strDriveType = "Unknown"
        Case 1
          strDriveType = "No Root Directory"
        Case 2
          strDriveType = "Removable Disk"
        Case 3
          strDriveType = "Local Disk"
        Case 4
          strDriveType = "Network Drive"
        Case 5
          strDriveType = "Compact Disc"
        Case 6
          strDriveType = "RAM Disk"
      End Select




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