Email Delivery Failure

[asasi]

Hello
I disabled Email feature in admin cp options but still I have many emails in admin box with this subject:

Mail Delivery System
----------------------------
A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  nono_ghalam@yahoo.com
    SMTP error from remote mail server after end of data:
    host c.mx.mail.yahoo.com [206.190.54.127]: 554 delivery error:
    dd Sorry your message to nono_ghalam@yahoo.com cannot be delivered. This account has been disabled or discontinued [#102]. - mta1078.mail.re4.yahoo.com

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for nono_ghalam@yahoo.com; Tue, 08 Mar 2011 00:38:19 -0500
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Date: Tue, 08 Mar 2011 00:38:19 -0500

Dear devoone,

You are subscribed to the thread "ظ?ط?ظ? ع?ط?ط?ط?غ? ط?ط?ظ? 1390! ط?ط? ط?غ?ط?ع?ط?ظ? ط?ظ?ط?.." by Mr soheil, there have been 13 posts to this thread, the last poster was Mr soheil.
http://www.meetland.ir/forums/%D8%B4%D8%A7%D9%8A%D8%B9%D9%87/29711-%D9%86%D8%A7%D9%85-%DA%AF%D8%B0%D8%A7%D8%B1%DB%8C-%D8%B3%D8%A7%D9%84-1390-%D8%A7%D8%B2-%D8%AF%DB%8C%D8%AF%DA%AF%D8%A7%D9%87-%D8%B4%D9%85%D8%A7.html

These following posts were made to the thread:
************
ظ?ط?ظ? ع?ط?ط?ط?غ? ط?ط?ظ? 1390! ط?ط? ط?غ?ط?ع?ط?ظ? ط?ظ?ط?..
http://www.meetland.ir/forums/%D8%B4%D8%A7%D9%8A%D8%B9%D9%87/29711-%D9%86%D8%A7%D9%85-%DA%AF%D8%B0%D8%A7%D8%B1%DB%8C-%D8%B3%D8%A7%D9%84-1390-%D8%A7%D8%B2-%D8%AF%DB%8C%D8%AF%DA%AF%D8%A7%D9%87-%D8%B4%D9%85%D8%A7.html#post1875977
Posted by: Mr soheil
On: Monday 7 March 2011 16:43

ط?ظ?ط? ط?ع?ظ? ظ?ط? ط?ط? ط?غ?ط? ظ?ط?ط?غ?ع?ظ? ظ? ط?ط?ظ? ط?ط?ظپ ظ?ط? ط?ط?ظ?ظ? ط?ظ?ط? ط?ظ?ظ? ط?غ?ط? ط?ط?ظ? ط?ط?غ?ط? ط?ظ? ط?ط?ط?ط? غ?ع? ظ?ط?ظ? ط?ظ?طھط?ط?ط? ظ?غ? ع?ظ?ظ?ط?. ط?ظ? ظ?ط?ط? ط?ظ?ط? ع?ظ? ط?ط?ظ?غ? ط?ط?ط?غ? ط?ط?ظ? 1390 ط?ط?غ?ط? ط?ظ?طھط?ط?ط? ط?ط?ظ?طںطں;y-x;
************

http://www.meetland.ir/forums/%D8%B4%D8%A7%D9%8A%D8%B9%D9%87/29711-%D9%86%D8%A7%D9%85-%DA%AF%D8%B0%D8%A7%D8%B1%DB%8C-%D8%B3%D8%A7%D9%84-1390-%D8%A7%D8%B2-%D8%AF%DB%8C%D8%AF%DA%AF%D8%A7%D9%87-%D8%B4%D9%85%D8%A7.html#post1875978
Posted by: Mr soheil
On: Monday 7 March 2011 16:45

How Can I disable email notification for forums and threads subscription?