Update: archaeological note: The OP's previous questions are Removing duplicates in large files and End of the Time Out Tireny.

If (as you've said before) your code is crawling or running out of memory sorting only 120000 email addresses, you've got a problem with your code. If you will please show what you've tried instead of just asking again, you will get better answers. (Update: my hypothesis that memory shouldn't be an issue is predicated on the knowledge that this is running on a web server.)

Also, some evidence that you've tried something like some of the solutions proposed would be appreciated. Why don't you give the solutions in Re: Removing duplicates in large files (a hash, or divide-and-conquer) a try (starting with the first and moving down)?