some one else has hacked and injected plugin all in one seo in my blog. he/she injected java script in Additional xxx Headers:
everytime i open my blog, this javascript will redirect my blog to another blog.
what should i do to prevent this attack?
Why do you assume All in One SEO Pack was hacked?
With this type of attack, it could have literally been any file on the server.
Remain calm and carefully follow this guide. When you're done, you may want to implement some (if not all) of the recommended security measures.