Nokia mobile firmware comes with physically different versions of same phone. Flash files are used for do software or update mobile old firmware. If your mobile working so slow or completely break at this stage you will need to flash your mobile phone by its latest flash files. You will need to download your mobile with its correct rm. If you will flash your mobile by different flash files your mobile will be going to dead. If you are flashing first time it is little bit difficult work for you because you will unable to find products in your pc by phoenix or other flashing boxes. If you have downloaded your mobile and you are ready for flashing like phoenix service one thing keep in your mind that please don't forget to make products folder in C:/program files/products.
Before flash please don't forget to take backup of your important data like images, messages and contacts. After flash you will lose your all of data and your mobile will restored in its original settings. Nokia mobile are divided into different groups for flashing. You can download latest flash files with out waiting longer. Flash files consist on mcu, ppm and cnt. So during downloading you will need to find these three files. Your mobile's all data is consist on these three files.