Hello! I have been reading about SPF records all afternoon. Depending upon which SPF tool is used to create the record, I have ended with the several different SPF records noted below. I am running a single SBS 2003 SP1 server with Exchange SP2, static IP address, PTR set up with ISP, MX and A records. SPF records via Microsoft SPF Wizard at [URL]http://www.microsoft.com/mscorp/safety/content/technologies/senderid/wizard/[/URL] v=spf1 mx ip4:xxx.xxx.xxx.xxx ptr:mail.mydomain.net mx:mail.mydomain.net -all v=spf1 mx ptr ip4:xxx.xxx.xxx.xxx mx:mail.mydomain.net -all SPF records via wizard at [URL]https://openspf.org[/URL] v=spf1 mx ip4:xxx.xxx.xxx.xxx ptr:mail.mydomain.net mx:mail.mydomain.net -all v=spf1 ip4:xxx.xxx.xxx.xxx a mx mx:mail.mydomain.net ~all v=spf1 ip4:xxx.xxx.xxx.xxx -all What do I really need to have? It seems as though v=spf1 ip4:xxx.xxx.xxx.xxx -all should be all I need. Why are all the other options presented? What do they all mean? Thank you for helping an SPF noob. Gregg Hill