Your computer will not detect the phone unless you install (also known as Samsung USB Serial Driver). These drivers allow the phone to enter “Download Mode” over USB.
The tool should automatically detect the device and start the process. Wait until the status bar turns green, indicating the process is complete. Alternative: Factory Reset samsung gtc3520 flash file and tool
However, like all electronic devices, the GT-C3520 is prone to software issues. Common problems include: Your computer will not detect the phone unless
: Flashing the firmware will erase all user data. Always attempt a Hard Reset first if you only need to clear a forgotten password. Battery Level Wait until the status bar turns green, indicating
The tool should detect the phone and the progress bar will turn yellow/blue. Wait until the process finishes and the progress bar turns Green or shows a "Done" message.