about Device start-up failed for n-gage

here' the tip

1.App closed main error
- run any explorer ( seleQ, Fexplorer, fileman)
- GO TO C:\system\bootdata
- DELETE: FirstBoot.dat
- turn off the phone and TAKE OUT THE MMC!!
- switch on phone(if u everything do right u will probably need to type in time and date)
- switch off phone again
- put in MMC back
- switch ON phone and..
NO MORE ERROR!!