Email status is "Pending Send"

Hi,

How to Send an Email to the corresponding Lead. I created a new lead and enter the Email Id in Email field and Save the Lead. Then i create a new Email to that lead, the Email Status is "Pending Send".

Whereas we give the CRM User Email Id the mail sent immediately.

Here the problem is other than CRM users , the mail cannot send.

Please clarify.

Thanks and Regards,