Xp doens't let nero burn cd anymore

[pakiya]

hello ,

i had winxp workin very fine with nero on my plextor 24x , today after a week , i have noticed that i cannot burn cd's any more properly , i mean , when comp is restarted and a cd is bunred , it's burned properly , after that if any cd is 2 be burned , after 100% when nero is closin the cd , i get an fixation error , any ideaz guys why this happens ???