Troubleshooting Domain and DNS Issues Print

Common Domain and DNS Problems

This guide addresses the most common domain and DNS issues encountered on Windows hosting.

Issue 1: "Domain Not Resolving" or "Site Cannot Be Reached"

Step 1: Check DNS Propagation

DNS changes can take 24-48 hours to propagate worldwide.

• Use online tools like whatsmydns.net to check propagation status
• Test from multiple locations/devices to confirm

Step 2: Verify DNS Records in Plesk

1. Log into Plesk
2. Go to Websites & Domains > select your domain
3. Click DNS Settings
4. Verify the A record points to your server IP
5. Ensure www CNAME or A record exists

Step 3: Check Domain Registration

• Verify domain hasn't expired at your registrar
• Confirm nameservers point to hosting provider
• Check for domain locks or holds

Issue 2: Subdomain Not Working

Creating a Subdomain in Plesk:

1. Go to Websites & Domains
2. Click Add Subdomain
3. Enter subdomain name (e.g., "app" for app.yourdomain.com)
4. Select document root folder
5. Click OK

Subdomain DNS Setup:

• Subdomains automatically get DNS records in Plesk
• If using external DNS, manually add A record for the subdomain
• Allow 15-30 minutes for DNS to update

Issue 3: DNS Changes Not Taking Effect

Clear Local DNS Cache:

Windows:

ipconfig /flushdns

macOS:

sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

Browser Cache:

• Clear browser cache and cookies
• Try incognito/private mode
• Try a different browser

Issue 4: Mixed WWW and Non-WWW Behavior

Ensure both versions resolve correctly:

• A Record: yourdomain.com → Server IP
• CNAME or A Record: www.yourdomain.com → Server IP or yourdomain.com

Redirect Configuration in web.config:

<rule name="Redirect to WWW" stopProcessing="true">
  <match url=".*" />
  <conditions>
    <add input="{HTTP_HOST}" pattern="^yourdomain\.com$" />
  </conditions>
  <action type="Redirect" url="https://www.yourdomain.com/{R:0}"
          redirectType="Permanent" />
</rule>

Issue 5: Email DNS Records (MX, SPF, DKIM)

Essential email DNS records:

When to Contact Support

• DNS records appear correct but still not resolving after 48 hours
• Server IP address confirmation needed
• Complex DNS configurations (split-horizon, etc.)