Build notification emails trigger new SMTP spam filter
I run a continuous integration system on my home server to build my projects. Whenever a build completes, it sends an email via Virgin SMTP to my gmail address, typically 4 at a time. Every morning it builds all projects, which results in 85 emails. This was working fine until recently.
A few days ago I saw "525 5.7.13 Account is Locked, change to new password is needed (VM303)" in Postfix logs. OK, so I changed the password in this additional Virgin account, no effect. I decided to make a fresh additional account for this purpose, and that worked for a couple of days. Now I'm seeing the same error again.
How can I fix this error in such a way that I never see it again?