Changing email system configuration

I have aMember installed, and it has been working okay. My problem is that when the email verification and the signup emails are sent, there are MANY email servers that bounce the email, so many of my members aren't getting the emails they need to be getting.

I'm thinking the emails are bouncing because of the FROM address, which is not our regular email address (info@mysite.com). Instead, the emails are sent from username@vps1234.inmotionhosting.com.

In email system configuration on the control panel, it's currently set to Internal PHP mail. I'd like to make it so that the verification and signup emails are sent from info@mysite.com, not the default server settings as it appears to be doing. I think that might fix our bouncing email problem.

BUT I have no idea how to set this up. I don't understand SMTP host or SendMail path. Help?

I need more help on this one.

I contacted my host, and they told me to make sure my outgoing email setting had the email address entered the way I want. That had already been done from the time I first installed aMember (http://img.skitch.com/20090811-tsgi1p87qp6w6ru2ib3w1mdfyj.jpg).

Yet my email verification and signup emails are not being sent from my info@mysite.com address as I imagine should be happening since I have that address in the "Outgoing Email Address" field. Instead, the emails are being sent from my VPS server which is not a valid email address (hence the bouncing emails).

Help?!

My host just sent this additional reply concerning my problem. Any suggestion? I've already set up aMember as far as I can tell. What should I do now?

"Since it's sending from username@vps1234.inmotionhosting.com, their servers must have done a reverse lookup. Meaning that their servers asked to see if the user username@vps1234.inmotionhosting.com was a valid user. Since it's not a valid user, their services would block you temporarily. You may want to make sure that your settings are setup correctly through your program so it's authenticating correctly or this issues will more than less happen again."

All fixed.

I submitted a support ticket and Alex fixed the problem. Unfortunately, I still have to contact a couple ISPs to get them to unblock our IP entirely.

"In case someone runs into this again in the future, what did Alex do to resolve the issue?"

bump

I run a dedicated server. On my previous hosting company, I had no problem sending mail from aMember using SMTP set to /usr/sbin/sendmail - recently I switched to Hostgator's dedicated hosting. They run a tighter ship there so now the only method that works is setting SMTP to 'localhost'. None of the other mail send options work.

If I try to set SMTP to /usr/sbin/sendmail I get the following error:

any idea why Alex?