Lenovo phones and tablets ship without a bundled desktop suite, which means Windows usually falls back to a generic MTP driver that handles file transfer but not ADB or Fastboot. Getting a Lenovo device to show up correctly in adb devices or fastboot devices requires the standalone Lenovo USB driver package, and on some builds a second pass through Device Manager to clear a stale driver binding.
Lenovo's own driver page is inconsistent between regions, and several of its download links point to installers last updated for Windows 7. In practice, two driver sources work reliably on current Windows builds:
Try the Google USB driver first since it is smaller and easier to keep updated. Fall back to the Motorola package only if Device Manager still shows a yellow warning icon after installing the Google driver.
Once installed correctly, the device should appear under Android Device > Android ADB Interface (or, in Fastboot mode, Android Bootloader Interface). Confirm with adb devices; a device ID with no unauthorized or blank serial confirms the driver bound correctly.
ADB driver binding does not automatically carry over to Fastboot mode — these are two different USB device classes on the same physical port, and Windows treats them as separate hardware. Boot the Lenovo device into Fastboot (usually Volume Down + Power from a powered-off state, though some Tab models use Volume Up), then check Device Manager again while it is connected in that mode. If it shows as an unrecognized device here even though ADB worked fine, repeat the driver update pointing to the same driver folder, this time targeting the entry that appears while in Fastboot mode specifically.
"This device cannot start (Code 10)" usually means the wrong driver architecture was selected, or a previous Lenovo PC Suite installation left behind a conflicting filter driver. Uninstall any Lenovo PC Suite or Lenovo Companion software entirely, reboot, and reinstall just the USB driver package.
Device is recognized for file transfer but adb devices shows nothing. This almost always means USB Debugging is off, or the "Allow the fingerprint" dialog on the phone was dismissed or never appeared. Revoke USB debugging authorizations under Developer Options, replug the cable, and accept the RSA key prompt on the device screen when it appears.
Driver installs but the device disconnects intermittently. This is typically a USB power management setting on the PC side. In Device Manager, open the properties of the USB Root Hub the device is attached to, go to the Power Management tab, and uncheck "Allow the computer to turn off this device to save power."
Run adb devices with the phone in normal mode and fastboot devices with it in bootloader mode. Both commands should return a serial number with no additional text. If either returns empty, the driver binding for that specific mode has not completed, even if the other mode already works — treat them as two independent checks rather than assuming one implies the other.