Error while creating spool file in oracle 10g

its the procedure to create the spool file
1 : open your sqlprompt
its look like
sql>
2 : Go to file at the left side at the top
3: left click on file there spool will be there
4: then click on spool it will show 2icon
1> spool files,2> spool of
click on spool files then set the location of spool file and save it
5:if every thing ok then in sql prompt write
sql> spool on
and press enter
simply it work and to off the spool write
sql> spool off