@echo off

rem Get the full path to the browser

rem Output from the REG command in XP differs from Vista/7.
rem Detect the operating system and adjust the number of tokens to retrieve accordingly.
for /F "tokens=2 delims=[]" %%A in ('ver') do (
	if "%%A" LEQ "Version 5.1.2600" (
		set _Tokens=4
	) else (
		set _Tokens=3
	)
)

rem Although the open command for the browser is kept in HKLM, a default browser choice other than Internet Explorer
rem is kept in HKCU. Check for the existence of a key in HKCU. If this fails, fall back on the key in HKLM.
set _DefaultBrowser=
reg query "HKCU\Software\Clients\StartMenuInternet" /ve >NUL 2>NUL
if errorlevel 1 (set _DefaultBrowser=HKLM\Software\Clients\StartMenuInternet) else (set _DefaultBrowser=HKCU\Software\Clients\StartMenuInternet)

set _BrowserKey=
for /F "tokens=%_Tokens%* eol=!" %%A in ('reg query "%_DefaultBrowser%" /ve') do (
	if "%%B"=="" (set _BrowserKey=%%A) else (set _BrowserKey=%%A %%B)
)

rem Once the default browser is known, obtain the path to the browser in HKLM.
set _BrowserPath=
set /a _DecTokens=%_Tokens%-1
for /F "tokens=%_DecTokens%*" %%A in ('reg query "HKLM\Software\Clients\StartMenuInternet\%_BrowserKey%\shell\open\command" /ve') do set _BrowserPath=%%B
echo Default browser=%_BrowserPath%

pause