Setting header for date to lower SpamAssassin score
===

I have used a testing service (verifier.port25.com) to check what was happening when emails were getting sent from my PHP script.  For some reason they were ending up in my GMail spam folder even though SPF and DKIM are enabled.

It turns out that the SpamAssassin score was 5.3, thus above the 5.0 benchmark.  Below you can see why.  The biggest problem is that I have a domain with 12 letters in it (it seems crazy to me that I should be punished for this but apparently 12 letter domains are popular among spammers).  As I don't want to have to change my domain, it looks like the next best option is to set a header for the date, but I am not sure how to do this.  Could someone help with this?


> 1.0 MISSING_HEADERS        Missing To: header
> 
> 0.0 HTML_MESSAGE           BODY: HTML included in message
> 
> -0.5 BAYES_05               BODY: Bayes spam probability is 1 to 5%
>                            [score: 0.0345]
> 
> -0.1 DKIM_VALID_AU          Message has a valid DKIM or DK signature from author's
>                            domain
> 
> 0.1 DKIM_SIGNED            Message has a DKIM or DK signature, not necessarily valid
> 
> -0.1 DKIM_VALID             Message has at least one valid DKIM or DK signature
> 
> 1.4 MISSING_DATE           Missing Date: header
> 
> 3.5 FROM_12LTRDOM          From a 12-letter domain