available download link for Nokia 1800 flash file (RM-653). before download this flash file at first check you device hardware problem. if device have any hardware problem you should fix this problem first then flash your call phone.
also take a backup your all of user data like contact, message etc. after flashing all data will be lost.
try always using upgrade flash file. upgrade flash file is batter for device performance. when you see your device turn on and only show nokia logo on screen, phone is slowly working, device hang any option is not working you need flash your device.
File Size :4 MB