? Troubleshooting Common Issues
Website Issues
500 Internal Server Error
Common causes and solutions:
- Incorrect web.config: Check syntax and validate XML format
- ASP.NET version mismatch: Verify correct .NET Framework version in Plesk
- Permission issues: Ensure IIS_IUSRS has read access to files
- Database connection: Verify connection strings in web.config
- Missing DLL files: Check bin folder for required assemblies
404 Not Found Error
- Check file exists in correct directory
- Verify URL rewrite rules in web.config
- Ensure default document is set (index.html, default.aspx)
- Check case sensitivity in URLs
- Verify virtual directory configuration
403 Forbidden Error
- Check directory browsing settings
- Verify default document exists
- Check IP restrictions
- Review folder permissions
Slow Website Performance
- Enable IIS compression in web.config
- Optimize images and media files
- Enable browser caching
- Review and optimize database queries
- Check resource usage in Plesk statistics
- Consider upgrading hosting plan
Email Issues
Cannot Send Email
| Issue | Solution |
|---|---|
| Authentication failed | Verify username/password, use full email as username |
| Connection timeout | Check firewall, use correct ports (465/587) |
| ISP blocking | Use alternative SMTP port 587 or 2525 |
| SSL/TLS error | Ensure SSL/TLS is enabled in email client |
Email Going to Spam
- Configure SPF records in DNS
- Add DKIM signing
- Set up DMARC policy
- Avoid spam trigger words
- Maintain good sender reputation
- Include unsubscribe link in newsletters
Database Connection Issues
Database Error Checklist:
- Verify database server is running
- Check database user permissions
- Confirm connection string accuracy
- Test with database management tool
- Review firewall rules for database ports
- Check database size limits
FTP Connection Problems
- Verify FTP credentials - Username and password
- Check FTP server address - Use IP if domain not working
- Confirm port number - Default 21, SFTP uses 22
- Passive/Active mode - Try switching modes
- Firewall settings - Allow FTP connections
- Check FTP user status - Ensure account is active
Getting Help
If issues persist:
- Check error logs in Plesk → Logs
- Enable detailed error messages temporarily
- Search our knowledge base for specific error codes
- Contact support with error details and steps to reproduce
