Unable to send hotmail

[ratnagopal]

I have flg mail accounts on my iPhone 4S.
Hotmail - 2, Gmail -2, Yahoo-1

From one of my hotmail accounts: "[email protected]", I am unable to SEND mails, but I am able to receive mails. There are no issues from all other accounts including my another hotmail account.

I have used my friend's iPhone 4S and added my hotmail account "[email protected]". I could send and receive mails. No issues.

I have done flg:

- deleted the said hotmail account and added again from hotmail and also MS exchange several times
- reset all settings of phone

Apple support team could not resolve for the past one month.

Can anyone help pls..