Conflict between codes

[Iggy]

Is there any reason that a code would no longer function properly when another code is entered? I am using a code that mimics the Facebook Like/Dislike feature. It worked well. I recently found code for a PM Notifier. That is placed in the Global Header. Once I did that, the like/dislike no longer functioned. The images were still there but when we click on them nothing happens. If you need a copy of the codes in order to see what the problem is. I will copy both here. I have saved them in my notepad.

[Charles Stover]

Yes, codes cancel themselves out all the time. It's generally because they'll use the same variable names.

[Iggy]

Thats a shame. I really like both of them.