scheduling batch files that set system variables

Hi,

I have a batch file that I want to schedule to set an
system variable (ie "set x = 12"). I can do it
successfully if I manually run the batch file. If I
schedule the batch file then the batch file runs without
any error, but the variable is not set. So if "x=11"
before running the scheduled batch file its still 11 even
after the batch file containing "set x = 12
" stmt. runs "successfully".

Any ideas is it running on a parallel universe
somewhere? :-)

Thanks.

Jay