[megaloman]

rango13,

Вот вариант

Код:

@Echo Off
cls

Call :Quote "Z:\Box_In\тра ля ля.txt" "Serial Number" "Rezult"
Echo [%Rezult%]     ErrorLevel=%ErrorLevel%

pause
GoTo :Eof

:Quote
	Set "%~3="
	For /F "usebackq tokens=2 delims=:" %%a In (`2^>nul FINDSTR /B /I /N /C:%2 %1`) DO (Call :OutQuote "%%a" %3 &Exit /B 0)
	Exit /B 1
	:OutQuote
		Set "OutRez=%~1"
		Call :OutRez0 "%OutRez:*"=% %2 
	GoTo :Eof
	:OutRez0
		Set "%~2=%~1"
GoTo :Eof