So some spam signups just happened (all username12345678@gmail.com format e-mail) This caused bounced mail to increase, causing Mailgun to block our domain to prevent it getting blacklisted.
So:
- Mail temporarily doesn’t work
- I closed signups for now
- I will ban the spam accounts
- I will check how to prevent (maybe approval required again?)
Stay tuned.
Edit: so apparently there is a captcha option which I now enabled. Let’s see if this prevents spam. Registrations open again.
Edit2 : Hmm Mailgun isn’t that fast in unblocking the domain. Closing signups again because validation mails aren’t sent
Edit 3: I convinced Mailgun to lift the block. Signups open again.
I solved this problem once. What you do is have a custom captcha that you code yourself. It can be as simple as “What is 2+3?” and have 10-20 questions that you rotate between. Most spammers will be too lazy to update their spambot.
Don’t just include it as text though. Rather, present the question as text in a picture.
I made one that phrased it as “The sum of 2 and 3”. Weeds out bots and less sophisticated people.