Overview 

In some cases, a website may load correctly using the Plesk preview link but fail to load or appear broken on the live domain. This usually indicates a difference between the server preview environment and the live DNS configuration.

Common Causes

1) DNS Not Pointing to the New Server

• The domain may still be pointing to the old hosting server
• Plesk preview loads directly from the new server, bypassing DNS

Check:

• Verify A record points to the correct server IP
• Confirm nameservers if recently updated

2) DNS Propagation Delay

• DNS changes can take up to 24–48 hours to fully propagate
• Some users may still see the old server

Symptoms:

• Site works for you (preview) but not for client
• Inconsistent behavior across locations/devices

3) Cached Content (Browser / ISP / CDN)

• Old content may be cached locally or via services like Cloudflare

Check:

• Clear browser cache
• Test in incognito/private window
• Disable CDN proxy (e.g., Cloudflare orange cloud → grey cloud)

4) Hardcoded URLs in Website

• Website may contain old domain or server references
• Common in WordPress migrations

Examples:

• Images loading from old domain
• Redirect loops
• Mixed content issues

⚠️ Important:
If fixing this requires database-wide search/replace →
OUT OF SCOPE — escalate 

5) SSL / HTTPS Mismatch

• SSL may not be installed yet on the new server
• Domain may force HTTPS but certificate is missing

Check:

• Ensure SSL is installed in Plesk
• Verify domain resolves to correct server before installing SSL

6) Configuration Differences (PHP / Plugins)

• Preview may load with different environment behavior
• Live site may trigger:
  • PHP version issues
  • Plugin/theme conflicts

Quick Troubleshooting Flow

1. Confirm domain points to correct server (DNS check)
2. Wait for propagation (if recent change)
3. Clear cache / test in private window
4. Check SSL status
5. Review for hardcoded URLs
6. Verify PHP version and plugins

When to Escalate

• Persistent issues after DNS propagation
• Suspected database-level URL issues
• WordPress critical errors
• Malware or corrupted files

Summary

Plesk preview bypasses DNS, so it can show the site correctly even when the live domain is still pointing elsewhere or affected by cache, configuration, or content issues.