I have been using VBA code in my Microsoft Access database to email reports via smtp.office365.com to our clients. This has been working perfectly for years when suddenly, some weeks ago, we started getting “transport error” messages. Microsoft say that the stmp server is fine. The vba code I use is common code used elsewhere in the world. An IT expert suggested that I consider whether Cloudflare may be the cause for the blocking for “factssa-com.mail.protection.outlook.com” is registered with Cloudflare.
What steps have you taken to resolve the issue?
Discussed with Microsoft and the Microsoft Access developer community
Was the site working with SSL prior to adding it to Cloudflare?
Yes
What is the current SSL/TLS setting?
Full
What are the steps to reproduce the issue?
If using the VBA code to send to a non-smtp.office365.com server, .e.g., gvam1287.siteground.biz, then it works perfectly.
factssa-com.mail.protection.outlook.com is outlook.com is owned by Microsoft. It uses azure-dns.org servers which are managed by Microsoft and it resolves to IP addresses managed by Microsoft. factssa.com uses Cloudflare. It’s Mx record resolves to factssa-com.mail.protection.outlook.com.
However your code is using smtp.office365.com which is definitely Microsoft, not Cloudflare.
You’ve got an open thread and example of a working config using port 25 instead of the 465? If it won’t work under either at least it’s easier for you to do a packet capture to determine the issue wiht your communication with the server if the VBA error isn’t straightforward enough. But it’s a code/server/config problem unrelated to Cloudflare.
