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Driver · Windows

Fix: CP2102 USB to UART Bridge Controller — driver not installed (Code 28)

Windows shows “CP2102 USB to UART Bridge Controller” with a yellow warning and no COM port. Install the Silicon Labs CP210x VCP driver and replug.

ESP32 DevKit V1 (CP2102)NodeMCU ESP8266 (Amica, CP2102)ESP32-CAM-MBCP2102 USB-TTL adapterUpdated 3 Nov 2026

Community draft — report a mistake

What you see

OutputOutput
Device Manager → Other devices
  ⚠ CP2102 USB to UART Bridge Controller
     Device status: The drivers for this device are not installed. (Code 28)
     There are no compatible drivers for this device.

The CP2102 from Silicon Labs is the USB-to-serial chip on many ESP32 DevKits, Amica NodeMCUs and USB-TTL adapters. Without its driver Windows lists the chip by name under “Other devices” but creates no COM port, so the IDE has nothing to upload to.

Install Silicon Labs’ CP210x driver and the board appears under Ports. If your board turns out to carry a CH340 or CH9102 instead, see CH340 driver not installed.

Quick fix — try in order

  1. 1

    Install the CP210x Universal Windows Driver from Silicon Labs

    Download “CP210x Universal Windows Driver” (link below), extract the zip, right-click silabser.inf → Install. Or use Device Manager → Update driver → Browse → the extracted folder.

  2. 2

    Unplug and replug the board

    Device Manager → Ports (COM & LPT) should now show “Silicon Labs CP210x USB to UART Bridge (COMx)”. Select that COM in the IDE.

  3. 3

    Still Code 10 or no port? Try the older VCP driver

    Some counterfeit CP2102 chips don't work with the newest driver. Silicon Labs' download page also lists the legacy “CP210x VCP Windows” package — uninstall the current one (tick delete driver) and install that.

  4. 4

    Check the chip really is a CP2102

    Read the tiny square chip next to the USB socket. If it says CH340/CH9102 instead, you need the WCH driver.

Why it happens

Why didn't Windows install it automatically?

Windows Update usually does, but offline PCs, college lab machines with updates disabled and stripped-down Windows installs often don't.

CH9102 looks like CP2102

Newer ESP32 boards use WCH's CH9102F in the same package. It shows up as “USB Single Serial” and needs the CH343/CH9102 driver from wch-ic.com.

Board-specific notes

NodeMCU ESP8266: “Amica” NodeMCUs use the CP2102; “LoLin V3” NodeMCUs use the CH340. See the NodeMCU page.

macOS: macOS 11+ includes a CP210x driver; the board appears as /dev/cu.usbserial-0001. Install Silicon Labs' driver only if it doesn't.

Drivers — official sources only

CP210x (Silicon Labs)silabs.comCH340 / CH341 (WCH)wch-ic.com

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