update bios Dell inspiron 15 3521 without battery

[DeathBringer]

Try
3521A12.exe /forceit
Forcing a BIOS Update without the AC adapter attached on Dell Laptop

[kppus]

same error.........

i have the original backup bios https://www.sendspace.com/file/oicilp     ,how to instal this?

[miant]

Had the same problem. Here is a working solution for DELL Inspiron 3521.
1. You need to download the bios 3721A14.exe
2. Download the official bios 3521A12.exe or 3521A16.exe from DELL website.
3. Extract both downloaded archive files to different folders by winrar (for example, to folders \3721A14 and \3521A16).
4. Copy with replacement all .exe/dll/sys files from directory 3721A14 to directory 3521A16.
5. Find the [AC_Adapter] section in the platform.ini file  and set Flag=0 and BatteryCheck=0.
6. Run \3521A16\insydeflash.exe , the bios should update on reboot. Be careful and don't power off your laptop.