A new update for the Windows 10-powered Lumia 550 smartphone has been quietly released by Microsoft. The update bumps the firmware version of the handset from 15461.48007 to 15503.21007, while the OS version remains the same.
What's worth mentioning here is that the update is reportedly only available through the Windows Device Recovery Tool, meaning it isn't currently rolling over-the-air (OTA). Keep in mind that if you use the the Windows Device Recovery Tool to update your device, you'll lose all your data.
There's currently no official information on what the update includes, although given that it's already available via the recovery tool, an official announcement (followed by an OTA roll-out) shouldn't be far away.
Why isn't it functioning
installing a custom rom is ludicrous.. you may as well just give the people who made it your bank detials, logon details to every web service ect... as they will have ways of making money from their time and effort to make the rom in the 1st place......
Custom roms are indeed avalible for Windows Phone but its a work in progress with only few supported phone models