For me, it's a yes to 4 criteria (our EHLO host id does not explicitly contain smtp or mail).... Every single time I've run into problems, so far, where my clients have not received our email or we have had mail rejections, it's been a misconfiguration of email/spam software at the receiving end. It's hard to quantify the benefits of having an SPF record - although I hope its helping prevent our IP from being RBL'd due to abuse by others - but its easy to see the admin costs of having one and having to constantly chase up problems. -----Original Message----- From: nznog-bounces(a)list.waikato.ac.nz [mailto:nznog-bounces(a)list.waikato.ac.nz] On Behalf Of SIMON WALKDEN Sent: Thursday, 22 July 2010 6:11 p.m. To: Mark Wakefield Cc: nznog(a)list.waikato.ac.nz Subject: Re: [nznog] SPF Mail rejection I've seen a lot of clients' outbound mail rejected in the last 12 months due to SPF issues; particularly mail being delivered to secureMX, or Xtra. The plan of attack was usually: 1. do they appear on any RBL's? (self explanatory, I know, just thought I'd list it) 2. does the HELO ID of their server match the MX record for the domain? 3. does the MX record (and HELO ID) contain the terms 'smtp' or 'mail'? (strange I know, but it's made a difference) 4. does a PTR record exist for the mail server's FQDN? 5. does the domain have a valid SPF record? If all these criteria are met, you really shouldn't have any problems passing go & collecting $200. Love, Simon W