need help in modifying the subject line

Probably this will work.

@ECHO OFF
SETLOCAL ENABLEDELAYEDEXPANSION
FOR /F "tokens=5" %%i IN ("%2") DO SET STATUS=%%i
SET STATUS=!STATUS:~0,-1!
IF "%STATUS%"=="0" GOTO :EOF
IF "%STATUS%"=="90" GOTO :EOF
IF "%STATUS%"=="150" GOTO :EOF
IF "%STATUS%"=="157" GOTO :EOF
IF "%STATUS%"=="190" GOTO :EOF

FOR /F "tokens=1,2,3,4,5" %%i IN ("%2") DO SET SUBJECT=%%i failed %%j %%k %%l %%m


IF "%~4"=="" (
blat %3 -s %SUBJECT% -t %1 -i NetBackup -server smtp.moc.com -q
)ELSE (
blat %3 -s %SUBJECT% -t %1 -i NetBackup -server smtp.moc.com -q -attach %4
)

blat %TEMP%\nbmail.tmp -s %SUBJECT% -t %1 -server smtp.moc.com >> D:\BUR_Scripts\Reports\DR File Email\nbmaillog.txt
) ELSE (
blat %TEMP%\nbmail.tmp -s %SUBJECT% -t %1 -server smtp.moc.com >> D:\BUR_Scripts\Reports\DR File Email\nbmaillog.txt -attach %4
)