You can use Nokia Best (Infinity-Box) , JAF , or Phoenix Service Tool .
While many third-party sites host these files, the following are known community sources for the v6.20 firmware: Nokia C1-01 Flash File Without Password
: In the "Flashing" tab, manually select the following files from your extracted firmware folder: rm607__06.20.mcusw You can use Nokia Best (Infinity-Box) , JAF
Do not attempt to flash your Nokia C1-01 without the following items. Skipping steps can turn your phone into a paperweight. You can use Nokia Best (Infinity-Box)
Nokia C1-01, firmware, flash file, password protection, mobile repair, device security, flashing, BB5, Phoenix, Odin (note: not applicable), legal/ethical considerations.