Based on our record, Spam Check should be more popular than InboxKitten. It has been mentiond 3 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Inboxkitten.com - Free temporary/disposable email inbox, with up-to 3 day email auto-deletes. Open sourced, and can be self-hosted. - Source: dev.to / almost 3 years ago
Sorry, it is not required on all servers, but you can use a tenporary e-mail such as https://inboxkitten.com/ and it will work just fine. Source: about 3 years ago
You should check to see if the messages that are being sent contain any links that would be considered questionable/spammy. You can also try taking the content of one of the messages and checking it’s spam assassin score ( https://spamcheck.postmarkapp.com ). Source: over 2 years ago
Build a clean email that passes a spam check with flying colors (https://spamcheck.postmarkapp.com/) then use a warmup service like lemwarm, inboxally or neverspam as mentioned in the other comments. Source: almost 3 years ago
The issue sounds more email centric. You're likely hitting the Apache SpamAssassin limit on the remote email servers. Use https://spamcheck.postmarkapp.com/ to check the score of emails you've had declared spam, and follow recommendations to improve. Source: about 3 years ago
MailDrop - maildrop is a Mail delivery agent used by the Courier Mail Server. The maildrop MDA also includes filtering functionality. maildrop receives mail via stdin and delivers in both Maildir and mbox formats.
Phishero - Test your organisation's resiliency towards phishing attacks
10 Minute Mail - Temporary disposable e-mail service to beat spam. Avoid spam with a free secure e-mail address.
AeroLeads - AeroLeads is a lead generation software which finds prospects with email and phone number.
Mailinator - Any Inbox. Any Time.
Referrer Spam Remover - Remove spam bots from your Google Analytics data