In writing a letter (or email), is it correct to use "future tense" instead of using "present tense" in your greetings?

When writing email to friends I always use present or present continuous  tense in greeting such as I hope you are doing good  but in the end I might use future tense such as I hope you will do good in the exam. Tomorrow... Or I will meet you next Monday....Am I Right? 

The only scenario to use future tense in the greeting is when you are perceiving that the reader will be "opening your letter" after some time (a concept better suited to snail mail). In a way, you are saying "I am hoping you will be doing well by the time this letter reaches you". This also puts forth the notion that you think the reader is not doing well now.

 

I will also advise against using the word "fine" as it does not sound as good.

Hope you're fine,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

Thank you Experts for your answers, I really appreciate them.

If it is an email or letter to a friend you would use present greetings. But business emails or letters should be kept stictly professional.

2. Hope you're fine. is the appropriate one. Anyway when it is going to read by the recipient of the mail/email, it is present tense only for the person to read it as, so hope you are fine is correct.  Thanks.

I agree with experts answer. Thanks for the invitation. .

Usually, I'd stick to the jargon used 

However, I agree with  Asad Abbasi

I'd like to add another context when the writer of the letter is aware that the addressee is not in good health and hopes he gets well when he receives the letter

I would prefer to use the present indefinite sentence. But it depends on the context situation.

No, and how possibly can one do it - no, sir, you use usual phrases

It is not correct to use the "future" in writing a letter. You definitely need to use the present simple, the present perfect and the future with "will" often, and the past simple and the past perfect less often. In cases where a past simple or a present perfect verb can be used with about the same meaning, the present perfect is usually better in formal writing - "we have received your letter" sounds better than "we received your letter." Remember to use the past simple if there's a time reference, though - "yesterday we received your letter" is correct and "yesterday we have received your letter" is not. The past simple and past perfect should be used in conditionals and reported speech clauses. Remember to shift the "reported" tense back, as in "yesterday we were informed that you had been notified..." Avoid "going to" for the future - I can't think of a situation when I'd use it. Use "will" and use the passive voice if you're talking about plans; as in don't write "we are going to carry out an investigation" but "an investigation will be carried out." If there's a modal verb phrase available, use it – if you're applying for a job or something, "I would like" is always better than "I want", and "should you wish to..." is better than "if you want to..." etc. This kind of stuff is what sets formal language apart in English, more than verb tenses.