Many recipients receive my email (sent with my exchange account @agora-secureware.ch) directly in the Junk folder. Looking at the headers of these message we can see
Received-SPF: TempError (protection.outlook.com: error in processing during lookup of agora-secureware.ch DNS Timeout)
Other recipients (for example @gmail.com) receive the same messages correctly (and there, these SPF appear as successful).
I've asked our Email Hosting but they say that for them everything is configured correctly. The SPF record for our domain looks like:
agora-secureware.ch text = "v=spf1 mx a ip4:18.104.22.168/24 include:spf.iway.ch -all"
What could be the problem?
Thanks a lot for your support.