Hello I have A556E device after rooting , and going back to stock rom (relocking the bootloader , flashing the latest fw from odin) I'm getting error as "Connecting to server" , "Registration Failed" is there anyway to fix this
When you root and then return your Samsung A556E to stock ROM, errors like “Connecting to server” or “Registration Failed” usually mean the device isn’t fully restored to a clean, factory state. Even though you flashed the latest firmware with Odin and re-locked the bootloader, some remnants of the root process or mismatches in firmware (CSC, modem/baseband, or region settings) can prevent the phone from connecting to carrier servers.
✨Think of it like rebuilding a house: even if the walls look freshly painted (the stock ROM), if the wiring underneath (modem, CSC, bootloader state) isn’t aligned perfectly, the lights won’t turn on.
Here are a few key steps you can try:
Check the Firmware Package – Make sure you flashed the full 4/5-file firmware (BL, AP, CP, CSC, HOME_CSC) from your exact device’s region. Using the wrong CSC or partial package can break carrier registration.
Use CSC instead of HOME_CSC – Flashing with CSC (not HOME_CSC) will wipe the device completely and reset carrier/network configs, which often resolves registration issues.
Verify IMEI/Network – Dial *#06# to confirm your IMEI is intact. If it shows null or “unknown,” rooting may have corrupted the EFS partition, which stores network identity. In that case, restoring EFS from a backup or professional repair service may be required.
Factory Reset After Flash – Once you re-flash, boot into recovery and perform a manual factory reset. This clears any leftover data conflicts.
Carrier/Region Lock – Ensure the phone isn’t region-locked or carrier-locked; if it is, you may need the original SIM or an unlock code.
If all else fails, it’s best to re-flash the exact official firmware for your region from a trusted source like SamMobile or Frija and carefully redo the process. If the IMEI/EFS is intact, this usually brings the phone back to normal.
In short: the error means your device isn’t talking properly with carrier servers because of mismatched firmware or corrupted network data — a clean, region-matched flash with CSC (plus checking IMEI) is the most beautiful way back to stability.
Hello thank you for your reply I see the IMEI and there isn't problem also before returning to stock I have used Frija tool to retrieve the stock rom I'm using an app to check my CSC there doesn't seem to be a problem should I factory reset through recovery?
