[*] Take a Backup: If you are going to flash or install the above Firmware on the Nokia 2690 RM-635 device, then take a backup of everything because your data will be deleted or removed post flashing or installing the Firmware.
Nokia is the big corporation having millions of the users behind the success of the company. You would have known that Nokia brand was sold out to Microsoft in previous passed years. Though there was not like a permanent selling of the brand but using the name, specific time spam deal was there, and Microsoft launched many smartphones based on Windows Operating system. There were some gray reviews regarding the phones, many of the users were unhappy with the interface and some of them very extremely happy to get such type of environment. That is the professionalism when Microsoft leave the brand and started manufacturing their own mobile phone, they also refrain themselves to provide the flash files. So, they refuse to give the servers and all the previous links were removed from the official Microsoft website. Now, you are not able to download the Nokia Flash Files from any of the Microsoft websites, there are some other manual ways to download the flash files. But, all risky and can damage your system, if they got some infectious files within the flash files.
First, download the Phoenix software, and install it on your computer. When the installation will be completed, it will ask you to put the code of your brand. You can put the code from the behind of your mobile phone. When you will put the code, it automatically fetches all the required flash files to flash your Nokia mobile phone.
Gather all the tools required to flash your Nokia phone, get a data cable, fully charged phone which needs to be fixed, a computer installed Windows and all required software and driver. Connect that computer to your mobile phone, and click on the given button of flashing. It will ask you to select the flashing files, you can browse and select the files where you have saved the downloaded Nokia Flash files within your computer. And click on the flashing, though it will take some minutes to complete the task, you will get a new mobile phone, new OS with smooth interface.