The following was summarized from Microsoft Knowledge Base Article 165908.
Standard USB cables won't work "out of the box" with Cisco hardware because the router uses a specialized USB-to-serial UART interface. Without the correct driver: Your PC will show an "Unknown Device" in Device Manager. No COM port will be assigned.
The file is usually packaged as a .zip containing both x86 and x64 installers. asr9xxusbconsoledriverszip upd
The safest and most reliable way to obtain the driver is directly from the portal. Navigate to cisco.com. Search for "Cisco USB Console Software." Standard USB cables won't work "out of the
Are you having trouble with a specific or error code while trying to install this driver? The file is usually packaged as a
If you are working with Cisco ASR 900 series routers (like the ASR 901, 903, or 920), you’ve likely encountered the shift from traditional RJ45 console ports to the mini-USB console interface. To get your terminal emulator (like PuTTY or SecureCRT) to recognize the device, you need the specific Cisco USB console driver.
You’ll be unable to access the CLI for initial configuration or password recovery. Where to Find the "asr9xxusbconsoledriverszip" Update
Troubleshooting ASR 900 Series USB Console Driver Issues (asr9xxusbconsoledriverszip upd)