UsbTreeView started with the USBView source code from the DDK for Server 2003. Here are the improvements I've done:

• Informations from the Windows Device Management are collected and matched with the found USB devices; Therefore UsbTreeView can show the child devices, including drive letters and COM-ports
• Window position is saved
• Background color and font of the right pane can be set (the font shown in the screenshots is DOSLike 7)
• Keeps the tree item selection over refresh
• TreeView highlighting of arrived and removed devices
• Shows open handles on failed safe removal
• Way more descriptors are decoded, as Audio 2.0
• Hexdump of the descriptors can be shown
• Safe removal, device restart and port restart
• Extended USB information available under Windows 8 and 10 (taken from the latest USBView sample application)
• Extended information about host controllers
• Failed USB requests are re-tried in the background, e.g. if a USB mouse was moved while requesting its properties
• Toolbar with jump-lists for easily finding devices in complex trees
• TreeView with handmade 16x16 icons, USBView used 32x32 icons scaled down to 15x15
• many minor improvements

• No more enumeration of all devices on arrival and removal of a USB device
• Search function (not full text, only things like device ID, drive letter, volume name etc)
• Some new Keyboard shortcuts (Alt+D to open the drives list, Alt+O the Others list, Alt+S to focus the search edit, Alt+Left/Right to cycle thru the search hits
• Options not to expand empty hubs or hub with only empty hubs attached
• Options to jump to arrived and removed devices
• Option to expand tree items to make selected arrived and removed devices visible
• Option to rename tree items (press F2 or single-click it when selected)
• Uses Windows visual theme with option to turn it off

• Can write and read a report in XML format (not compatibel with USBview's)

• Bugfix: Minor fixes

• Bugfix: Crash on Windows 8, 8.1, Server 2008 when dealing with companion ports
• New: Highlight for companion ports (Win8+)
• New: Right-click -> Copy Tree from here can copy a full treeview screenshot

• Bugfix: since V3.4.0 copy tree to clipboard did not work
• Bugfix: since V3.4.1 possible crash when restarting a hub

• Bugfix: since V3.4.1 SuperSpeed ports got no 'S' icon and max speed shown as SuperSpeedPlus

• Bugfix: V3.4.1 crashed on pre-Win8 systems

• Bugfix: Child devices sorted by device id instead of kernel name, at least for devices the author came across with this leads to better sorting, e.g. for COM ports
• Bugfix: TreeView's context menu did not work on negative mouse coordinates (on screens left of the main screen)
• New: Shows a summary with the most interesting information
• New: Can shows sum of used endpoints of all devices attached to a root-hub in the tree-view
• New: Remembers which ports have ever operated at SuperSpeedPlus (because so far there is no way to request the capability)

• Bugfix: Crash with failed USB hub
• New: UVC 1.5 H.264 descriptors are decoded
• New: More device interface GUIDs are resolved
• New: Reporting a USB version of 2.0 is blamed as an error if the device does not deliver an 'other_speed' device_qualifier descriptor because USB 2.0 spec says 9.2.6.6: 'Devices that are high-speed capable must set the version number in the bcdUSB field of their descriptors to 0200H. This indicates that such devices support the other_speed requests defined by USB 2.0.'

• New: Contains nearly 12000 vendor names from usbif.json instead of 1000 from the former usb.if
• New: Option to allow only one instance running
• New: Nodes of devices with a problem show a tool-tip with a problem description

• Bugfix: Renamed tree items not shown with the customized name on startup

• New: Shows Registry flags under HKLMSYSTEMCurrentControlSetControlusbstorVVVVPPPP

• New: Sum of used endpoints shown for root-hubs
• New: Option to show the number of used endpoints in the tree
• Bugfix: Crashs on device removal

• Bugfix: Sometimes truncated XML report
• New: A selected tree node can be renamed by pressing F2 or single left-click it (needs admin privileges)

• New: Finds root hubs which are not the child device of their host controller (often seen on virtual USB over LAN)

• Bugfix: Text report by command-line did not work since V3.3.0

• Bugfix: Device arrivals not detected when registry contains wrong device path for a USB hub

• New: Can write and read a report in XML format

• Bugfix: Crash when showing open handle after failed safe removal of a device with a COM port
• Bugfix: MessageBox was shown after writing a report by command-line
• Bugfix: guidExtensionCode in 'Video Control Extension Unit Descriptor' was not shown
• New: Name of guidExtensionCode (e.g. 'YUY2') is extracted from the first four bytes of the GUID

• Bugfix: Some strings for Smart Card Functional Descriptor where shown as question marks
• Bugfix: UVC frame intervals where shown without fraction of milliseconds for continuous frame type

• Bugfix: UVC frame intervals where shown without fraction of milliseconds

• Bugfix: Under XP the UsbTreeView process did not end after using 'Safely Remove'
• New: Highlight color of selected item darker

• New: TreeView highlighting as known from the SysInternals ProcessExplorer
• New: On failed 'safe removal' it shows open handles found for the device ID Windows returns as VetoName
• New: Shows global registry USB flags under HKLMSYSTEMCurrentControlSetControlUsbFlags and HKLMSYSTEMCurrentControlSetServicesusbhubhubg

• New: Detects arrival of USB devices even its driver fails to start, e.g. if no driver is installed yet
• New: Detects childs of USB devices even they don't generate device notifications nor they are enumerated by SetupDiGetClassDevs (seen on Arduino Micro)

• Bugfix: Device Qualifier Descriptor was requested even the device is running at SuperSpeed

• New: Option to show the port chain instead the port number in the tree
• Bugfix: Some hexdumps where missing
• Bugfix: Device Qualifier Descriptor was requested for USB 1.x devices

• New: Copy tree to clipboard function
• New: Text copied to clipboard as HTML fragment enclosed in <pre> tags to get a monospaced font offhand
• New: SmartCard Reader Feature Descritpor decoded
• Bugfix: Volume of CDROM drives not recognized on arrival

• Bugfix: Wrong value shown for Clock Selector in Audio Control Clock Selector Unit Descriptor 2.0
• New: Full enumeration when missing USB device notifcation is detected (workaround for SILEX USB Device Servers)

• Bugfix: Occasional crash on safe removal
• Bugfix: Since V3.0.6 no device information for UHCI controllers under Windows 2000
• Bugfix: wPacketSize decoded wrong if SuperSpeed device reported a Device Bus Speed of 0x02

• New: Can show multiple Configuration and Other-Speed-Configuration Descriptors
• New: TreeView sub-menu to copy some id strings to clipboard

• Bugfix: Removal of storage volumes not handled correctly
• New: Project is UNICODE now, so non-ASCII string descriptors are shown correctly even the Windows ANSI codepage cannot
• New: Improved robustness when decoding invalid descriptors
• New: Option 'Always On Top'

• Bugfix: No more font change in the text pane when hitting some special charaters

• New: Improved detection of arrival/removal of child devices
• New: Devices in low power state and problem code 0 get a 'D1', 'D2' etc icon instead of an exclamation mark
• New: Workaround for a strange phenomenon: On some Windows device notifications come with wide strings even RegisterDeviceNotificationA was used; This is dealt with now.

• New: Support for virtual USB Controllers where Hostcontroller and Root-Hub are one and the same device

• New: Port property PortConnectorIsTypeC (Win10 only)

• New: Device Manager problem numbers shown in the treeview icons

• New: Search hits get highlighted in the text pane (which is a RichEdit control now)

• Bugfix: Dropdown lists not refreshed on device arrival and removal

• Bugfix: Crash on full refresh

• New: No more enumeration of all devices on arrival and removal of a USB device
• New: Search function (not full text, only things like device ID, drive letter, volume name etc)
• New: Toolbar controls shrink if required
• New: Some new Keyboard shortcuts (Alt+D to open the drives list, Alt+O the Others list, Alt+S to focus the search edit, Alt+Left/Right to cycle thru the search hits
• New: options not to expand empty hubs or hub with only empty hubs attached
• New: options to jump to arrived and removed devices
• New: option to expand tree items to make selected arrived and removed devices visible
• New: Uses Windows visual theme with option to turn it off

USB 2.0
Here we have Win7 Computer with an Intel P35 chipset which has 8 USB 2.0 High-Speed capable ports. The 8 physical ports are split here: 4 USB 1.1 controllers deal with USB low and Full-Speed devices while one USB 'Enhanced' controller deals with the High-Speed devices. I don't know why the 1.1 ports are split over 4 controllers with 2 ports each. Since all manufactures do this, there must be a good reason...
The USB High-Speed controllers usually have the keyword 'Enhanced' in their device name. Since Vista the 'USB Hub Capabilities' can be checked for the 'HighSpeed' flag.
At port 1 of the Enhanced controller there is a USB High-Speed hub attached and at his port 4 there is a USB mass storage device attached which is thanks to USBDLM mounted at drive letter Z: again. Here it is running at High-Speed.
Newer Intel chipset have no more USB1 root hubs. Instead there are two integrated standard hubs which translate Low and Full-Speed into High-Speed. Intel calls them 'Integrated USB 2.0 Rate Matching Hub'.

USB 3.0
Here we have a Win8 Computer with a Texas Instrumens TUSB7340 USB SuperSpeed controller card. Windows 8 has native support for USB 3.0 SuperSpeed and an enhanced USB stack which delivers more information, e.g. which speed each port supports. Therefore UsbTreeView can show a 'H' in the icon of the high-speed ports and an 'S' for the SuperSpeed ports. Still missing is the information about the supported SuperSpeed (5, 10 or 20 GBits/s)
The TUSB7340 has 4 physical ports. 4 logical ports are for low, full and high-speed devices and another 4 for SuperSpeed devices. Windows 8 also delivers information about which logical ports belong together. In the screenshot you see that the selected port 4 has the CompanionPortNumber 8, this means that port 4 and 8 share the same physical port.

USB 3.0 Hub
USB3 hubs are in fact two completely independend hubs, one for SuperSpeed and the other one for High, Full and Low-Speed devices.
The only thing in common is that both appear connected to ports which are mutual 'companion ports'.
Here port 20 is the companion port of port 9 and vice versa:

Intel Series 8 xHCI Controller
Here we have a bunch of yellow exclamation marks on a Intel Series 8 xHCI controller on a Asus H81-Plus board. Its ports 11 to 15 have a connection status 3 'Device general failure' which leads to the yellow exclamation marks in the tree view.
Intel's xHCI controllers are quite flexible and need a correct initialisation by the mainboard's BIOS. I don't know this is Intel's or the BIOS maker's fault. As long as all physical ports work as expected this is a cosmetic problem.

The BadUSB device demonstrated by Adam Caudill and Brandon Wilson at github.com looks like this: Note that it is a Composite Device, that is has two child devices - the expected disk and the potentially bad keyboard.

A regular USB drive look like this: USBDLM can ask on arrival of a new keyboard or network device if it shall be activated:
https://www.uwe-sieber.de/usbdlm_help_e.html#badusb

Download latest release:
Win32:
https://www.uwe-sieber.de/files/UsbTreeView_Win32.zip
(~340KB)
x64:
https://www.uwe-sieber.de/files/UsbTreeView_x64.zip
(~340KB)
Download old V3.0.2 (last without RichEdit control):
https://www.uwe-sieber.de/files/usbtreeview302.zip
(~299KB)
Download old V2.6.1 (last 2.x):
https://www.uwe-sieber.de/files/usbtreeview261.zip
(~273KB)
Download old V2.0.2:
https://www.uwe-sieber.de/files/usbtreeview202.zip
(126KB)
Download old V1.5:
https://www.uwe-sieber.de/files/usbtreeview150.zip
(96KB)

Other old releases are available under the usbtreeviewNNN.zip names.

UsbTreeView is Freeware.
Allowed:
- usage in any environment, including commercial
- include in software products, including commercial
- include on CD/DVD of computer magazines
- distribution by means of packet managers
Not allowed:
- modify any of the files
- offer for download by means of a 'downloader' software

I don't ask for donations but some users insist, so:
PayPal

Information about serial COM ports:
COM Port Info
Information about drives:
USB Drive Info