Renames a bunch of files that have an underscore as the first character to the name without the underscore. The extension and first character are changeable - also could be multiple first characters.
setlocal enabledelayedexpansion
for /r %%i in (*.html) do (
set a=%%~nxi
set b=!a:~0,1!
if /i NOT "!b!"=="_ " (
del "%%i"
) else (
set c=%%~nxi
set d=!c:~1,1000!
rename %%i !d!
)
)