#Troubleshooting
Troubleshooting is the step-by-step process of finding the real cause of a problem instead of guessing at fixes. For websites and e-mail that means reading error messages, headers, logs and DNS records carefully. A good troubleshooting routine starts with the simplest checks and changes one thing at a time. It also records what was changed, so that a fix can be confirmed or reversed. The articles under this tag walk through common failures and the checks that reveal their causes.
1. 10. 2026 · Čtení: 8 minSMTP Ports 25, 587 and 465: Which One Should You Use?
Port 25, 587 or 465? Learn what each SMTP port is for, which to use for your website or mail app, and how to…
1. 10. 2026 · Čtení: 8 minCORS Explained: The Misconfigurations That Expose Your Data
CORS decides which other websites may read your responses. Learn how it works, the common misconfigurations that leak data, and how to set it…
1. 10. 2026 · Čtení: 8 minGoogle Traffic Dropped? How to Find the Cause Step by Step
Organic traffic fell suddenly? Work through tracking, technical errors, indexing, updates and competition in order to find the real cause before fixing.
1. 10. 2026 · Čtení: 9 minWhy Your PageSpeed Score Changes Every Time You Test
Your PageSpeed score jumps between tests even when nothing changed. Here is why lab scores vary, what is normal, and how to measure speed…
30. 9. 2026 · Čtení: 8 minGreylisting Explained: Why Some Emails Arrive Late
Greylisting makes a mail server refuse the first message from an unknown sender until it retries. Learn how it works, why it delays email…
29. 9. 2026 · Čtení: 8 minBackscatter: Why You Get Bounces for Emails You Never Sent
Getting bounce messages for emails you never sent? That is backscatter from spoofed spam. Learn how to tell if you were hacked and how…
13. 9. 2026 · Čtení: 7 minHow to Test Email Deliverability Before You Hit Send
How to test whether your e-mails will reach the inbox: header checks, seed tests across providers, DNS checks and the limits of each method,…
11. 9. 2026 · Čtení: 8 minDKIM Failing? How to Troubleshoot dkim=fail and dkim=none
A step-by-step guide to fixing DKIM failures: missing keys, wrong selectors, truncated records, modified messages and signatures that use the wrong domain.
31. 8. 2026 · Čtení: 7 minOrder Confirmation Emails Not Arriving? Fix Your Shop’s Mail
Online shop order and shipping e-mails missing or in spam? Learn why transactional mail fails, how to authenticate it and how to separate it…
28. 8. 2026 · Čtení: 8 minHow to Read Email Headers to Check SPF, DKIM and DMARC
E-mail headers show exactly why a message passed or failed authentication. Learn how to open them in Gmail and Outlook and read Authentication-Results.
27. 8. 2026 · Čtení: 8 minEmail Forwarding and Authentication: SPF, SRS and ARC Explained
Forwarded e-mail often fails SPF and sometimes DMARC. Learn why forwarding breaks authentication and how DKIM, SRS and ARC keep forwarded mail deliverable.
25. 8. 2026 · Čtení: 7 minEmail Bounce Codes Explained: Hard vs Soft Bounces and Fixes
Learn to read e-mail bounce messages: the difference between hard and soft bounces, what common SMTP codes mean and how to fix the causes…