After that you gotta modify the file
xfire_games.ini , usually located at: C:\ProgramData\Xfire
Remember to make a backup copy, its always good, hun.
Locate the Battlefield 3 command line and change it to this:
[6894]
LongName=Battlefield 3
ShortName=bf3
LauncherDirKey=HKEY_LOCAL_MACHINE\SOFTWARE\EA Games\Battlefield
3\Install
Dir
LauncherUrl=http://battlelog.battlefield.com/bf3/
DetectExe=bf3.exe
Launch=%UA_LAUNCHER_URL% %UA_LAUNCHER_EXTRA_ARGS%
%UA_LAUNCHER_NETWORK_ARGS%
InGameRenderer[0]=D3D9
InGameRenderer[1]=D3D10
InGameRenderer[2]=D3D11
InGameFlags=USE_PRESENT|ENABLE_MOUSE|USE_WINDOWS_INPUT
AlwaysFullScreen=1
Restart your XFIRE.
go to TOOLS > OPTIONS
Select GAMES, wait for the detection, select the Battlefield 3
be sure that the in-game renderer option points to D3D11
*To avoid LAG during the game*