Linux server-generated email from web forms discarded as spam (sendmail,php)

I am using Typo3 CMS to generate simple web mail forms.  I am using a dedicated server at GoDaddy running Fedora.  Many of the server-generated emails are being discarded to spam when sent to hotmail, yahoo, etc.  These are essential for my clients to get as they are interested buyers filling out a simple web form.  When sent to a hosted Exchange server it's even being culled to the point it doesn't even show up in the spam box... like it was never even sent.

So let's list these questions in order so they can be addressed separately.  As you can see I have looked into many different possibilities, but am so confused now that I just need clarification on which direction to go.  I would prefer sending direction from the server instead of doing an external SMTP server but I guess whatever it takes is what I will do.

1. Is it possible to send legitimate server generated email from web forms that reliably do not get sent to spam?

2. Can I use the email of the person filling out the form in the "from" and "reply-to" fields of the server generated email without it going to spam?

3. I believe sendmail is what is being used to send mail.  In php.ini, "sendmail_path = /usr/sbin/sendmail -t -i".  When I do "ps aux | grep sendmail", sendmail appears to be running.  When I do "/sbin/service sendmail status" I get "sendmail is stopped, sm-client is stopped". How can I tell for certain that I'm using sendmail?

4. I have looked extensively on this forum as well as the web and am purely confused now.  I have configured before to use an external SMTP server that didn't require authentication.  Is it possible to use an external SMTP server that requires authentication using sendmail and will this potentially reduce my possibility of getting sent emails going to spam or will correctly sent server-generated emails be just as valid?

5. Does the hostname of my server matter to the spam ranking of server-generated email.  Currently if I do not specify a from address it gets sent as
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ridConnect With a Mentor Commented:
I THINK the reverse DNS is performed on the server hostname/IP, not on any data in the FROM: field of the messages.
This sounds to me like you are on a shared server that possibly has been a source of spam and therefore the default mail headers you are sending are also considered spam.

Solutions include checking if the headers in your received emails from your scripts are properly formatted to say who they are from etc. If wrong or default you can change some of them.

If you have a received email post the headers here so someone can look at them.

I know TYPO3 quite well - you didn't specify how you are creating your web forms. From scratch in PHP, using an extension? which one.

matt1237Author Commented:
I am using the default Typo3 mailform, so there should be no trouble with header formation.  Here's my configuration:

Name | name=input
Email Address | email=input
Comments | comments=textarea
 | formtype_mail=submit | Send
 | html_enabled=hidden | 1
 | subject=hidden | Email from
 | from_name=hidden | My client's business name
 | from_email=hidden |
 | replyto_email=hidden |
Also I set the recipient-email field to:,

This is a dedicated server so I wouldn't think it would be effected by other spammers as there has been NO spamming ever on this GoDaddy dedicated server since I purchased it.  Notice that I have also tried omitting the last 3 configuration lines which then makes the email from field be automatically set to whatever was was entered by a web user into the "Email Address" field.  Both ways are being completely ignored by my external hosted MS Exchange server email account but 90% of the time works with my hotmail account.

So, the question is... what is causing these emails to "disappear"?
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"5. Does the hostname of my server matter to the spam ranking of server-generated email.  Currently if I do not specify a from address it gets sent as"

the hostname of your  server matters, if there's a reverse DNS lookup performed on its IP and it fails, mail will probably be discarded as spam.

Some spam filters may actually dislike a sender that is "anonymous" and cause trouble for you; that sort of sender may add to the spam level rating.
matt1237Author Commented:

You have answered my question and I will award you points, but I have one final question that remains and you or someone else can answer this.

I have now changed my server's hostname to be "" and reverse DNS now works and emails are being successfully delivered to my Exchange server!  I also have many of my client's domain names and website hosted on this same server.  They all resolve to the same IP as  Can I use the from address of safely and still have reverse DNS work out and not get spam filtered?
matt1237Author Commented:
Thank you Rid.  I will ask about the reverse DNS lookup on an email in a new question posted here... 
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