Thanks sir .

@Malik,

Suppose you register with email [email protected] and then after activation you changes email to [email protected] I don't think we need to send confirmation for email change.

The main thing is user should not able to use email of other user that already member of your site, and OSSN didn't allows to use the emails that are already used, so you don't need to worry about it. I am agree with what @Zet, said in reply.

We may implement a feature that requires a old password to edit a profile.

You are right sir but
When user change email
Example [email protected] to [email protected] i think for changing email conformation is required .
For cancel /delete gmail also facebook account not delete when we delete gmail account Facebook account work fine.
But when we change or add another email conformation is required for security's
I hope you will be understand

Ah, I'm beginning to understand what you want: You want to make sure that all your members are using valid email addresses. But I give you one example showing that it's hopeless - even with a confirmation feature installed:

• Your friend Ali Raza had registered with [email protected]
• His address was valid and everything looks fine
• Next thing Ali does: He cancels his gmail account
• [email protected] is invalid now
• but Ossn and you wouldn't notice, because Ali has not changed his address on your website

You see, Ali can still fool you if he likes, and the confirmation feature will be of no help in a case like that.

Sir you are true but my website is not limited to my friends
After sometime when i register to .net domain i attach link my this website to my business website i think anyone able to register to my website
And its difficult to see who using valid email.

I still don't understand your logic.

As long as your friend Ali Raza is able to login to your website, he can do what he wants - no matter what email he is using.

But otherwise as you wish
I try my self.
.ok for reply

Sir if confirmation required user can not access to other email.
Its security's for hackers .
I know who this person he is my friend ali Raza
There is only 6member in my site
If its its more then 200+ there is difficult to see who use valid email address .
I think conformation is need

Ok, I see.
But in which way is this threatening your website's security?

Sir one register user my website register form gmail i see form admin panel
after some day i see he change email to [email protected]