Make sure that google's reason is still the SPF record.
There are lots of other things that Google will use to classify email as SPAM.
Possibly relevant in your case:
* IP Addresses from ranges of IPs assigned by your ISP to residential internet connections
* Mismatch between your server's DNS, HELO and PTR records
Way too much detailIP Address Space- If your IP address belongs to a range that has been identified by your ISP, or by any of several spam filters (spamhaus etc) or by Google as belonging to an IP Address space used mostly by residential users some of whom have dynamic IP addresses, your email may go to SPAM.
- The recourse in this case is to pay your ISP for an IP with a different reputation, or to relay your email through an outgoing service
--> If you start relaying email through a service you will need to adjust your SPF recordHELO- whatever your server uses as its HELO string needs to return your server IP address in a DNS lookup
- Some services also insist that the name used for HELO return an "A" record, and not a "CNAME" record
- SME 'HELO' is set using qpsmtpd->HeloHost, defaulting to DomainName if qpsmtpd->HeloHost is not set:
{ $qpsmtpd{HeloHost} || $DomainName }
nslookup $(config getprop qpsmtpd HeloHost || config get DomainName) 4.2.2.2
PTR- your IP address needs to have a PTR record
- The name returned for the PTR lookup for your IP needs to resolve to the same IP
- The PTR record for your IP is controlled by whoever owns the IP address -- almost certainly your ISP. Changing or setting a PTR record for your IP would require asking the ISP, who may or may not do what you ask.
# nslookup -type=txt apache.com
apache.com text = "v=spf1 +a +mx +ip4:67.227.199.17 ~all"
# nslookup -type=ptr 17.199.227.67.in-addr.arpa
17.199.227.67.in-addr.arpa name = host2.accelrf.com.
# nslookup host2.accelrf.com
Name: host2.accelrf.com
Address: 67.227.199.17
# curl ipinfo.io/67.227.199.17/org
AS32244 Liquid Web, L.L.C
# nslookup -type=soa 17.199.227.67.in-addr.arpa
# (nothing, so chop off the last octet
# nslookup -type=soa 199.227.67.in-addr.arpa
Non-authoritative answer:
199.227.67.in-addr.arpa
origin = ns.sourcedns.com
mail addr = admin.sourcedns.com
serial = 2023050301
refresh = 28800
retry = 7200
expire = 3600000
minimum = 14400