If Windows shows a yellow exclamation mark next to an "Unknown Device" or "Spreadtrum Phone" entry:
If the device shows up as "Unknown Device" or under "Other Devices" with a yellow exclamation mark:
: Get the latest SPD Driver R4.20.0201 (or a version matching your specific OEM like Lenovo or Intex) and extract the files to your desktop. sprd u25 diag driver work
What specific or service tool are you trying to connect?
The SPRD U25 Diag Driver is a critical component for servicing mobile devices powered by Spreadtrum (now Unisoc) chipsets. It creates a diagnostic interface between your computer and a device connected in diagnostic mode. Technicians and developers use this virtual COM port to repair IMEI numbers, flash firmware, unlock bootloaders, and run deep system diagnostics. When the driver fails to work properly, your servicing tools will not detect the phone, halting the repair process. How the SPRD U25 Diag Driver Works The Role of Diagnostic Mode If Windows shows a yellow exclamation mark next
: Ensure the phone is in "Diag Mode" (often enabled via *#*#83781#*#* or specific key combos).
Sometimes a USB 3.0 port (blue) causes issues. Use a USB 2.0 port if available. 4. Manually Assign COM Port If another program is using the assigned port: It creates a diagnostic interface between your computer
Hold down the key while clicking Restart in your Windows Start Menu.
If this guide helped you, consider contributing to the open-source SPRD diag tooling project. For persistent issues, capture a USB trace via Wireshark with the usbmon module and consult the developer forum.