The second is correct. This is an embedded question, and it follows the same rule as reported speech in that you need to have standard sentence word order rather than question word order: Direct speech : 'When will you visit me?' Indirect speech: I asked her when she would visit me. Embedded question: I'd like to know when you will visit me. This is the same for all embedded questions of this type: Please tell me when you will visit me. Let me know when you will visit me. Can you tell me when you will visit me?

Both are a little awkward, but the first is the best choice. "I'd like to know when will you visit me?"..In natural conversation, you would probably just say "When can you visit me?".

It would be more natural to drop the "I'd like to know" and just say "When will you come visit me?".

Thank you. Unfortunately I can't make your answer the best one because I've already chose C.J (it was a bad choice obviously :( )

Thanks for the support, Jmat. Becia, you are of course free to choose whichever answer you like as your Best Answer. That's entirely up to you. But please note that if you were to write the embedded question 'I'd like to know when will you visit me' in an English test, it would definitely be marked wrong.