That has got to be terribly frustrating. From what I have read, their rejection letter is a boiler plate that they send to everyone they reject, giving no clue as to what went wrong.
A blog named eHarmony Blog, but which is unaffiliated with eHarmony, has done some research to offer some insight in the rejections:
Reason #1. You said you are separated or married on page 1. 30% of eHarmony rejects fall into this category, according to a May 2007 article in the Washington Post.
Reason #2. You said you are below 20 on page 1. 27% percent fall into this category.
Reason #3. You said you were married more than twice on page 1.1
Reason #4. Your answers don’t tally, i.e., (a) you clicked randomly or (b) for example, you put “1″ under Aloof on page 1, but checked “Outgoing” on page 6. 9% of rejects fall into this category.
Reason #5. You scored low on the following traits — eHarmony calls them dimensions:
* Self-Concept (how you perceive yourself)
* Emotional Status (feeling happy, fulfilled and hopeful)
* Character (honesty and trustworthiness)
* Obstreperousness (the black hole dimension)
* Character (honesty and trustworthiness)2
* Emotion Management: Anger (expressing negative emotions constructively)
* Conflict Resolution (resolving issues).
* Family Background (happy childhood and supportiveness of your parents)