I am using Amazon EC2 Instance for one of my project, I have installed LAMP on linux server and now while I am trying to send email using simple function it is not sending email also is not giving any error for that.
Things I have done so far.
Although your problem relates to Sendmail have you tried following Amazons Documentation?
This uses postfix but it seems like a better alternative and there's help readily available for it.
You also can use SMTP as Amazon SES supports this:
I know this doesn't directly answer your question. You might just need to configure the