How to Fix Email Deliverability Issues for Hosting Providers

Solving Email Deliverability and Security Challenges for Growing Cloud Hosting Provider

Client
:
A managed cloud hosting company serving 500+ e-commerce and SaaS companies across the USA
Objective
:
Resolve critical email infrastructure issues affecting customer notifications and implement enterprise security for business operations
Delivered by Nuventure
:
Complete email infrastructure redesign with Exchange optimization, SendGrid integration, and comprehensive security framework

Customer notification emails (billing alerts, server status, support tickets) frequently delayed or undelivered

Shared hosting infrastructure IP addresses blacklisted due to client spam activities

On-premises Exchange server struggling with 10,000+ daily automated notification emails

Email spoofing attacks targeting customer accounts using company domain

Support team emails to customers blocked by spam filters affecting response times

No encryption for customer communications containing sensitive server credentials

Multiple phishing attempts compromised two employee accounts exposing client data

Separated transactional notification emails from internal business communications

Implemented SendGrid integration for customer notification delivery

Optimized on-premise Exchange 2019 for internal team communications only

Deployed Barracuda Email Security Gateway with domain-specific filtering rules

Implemented DNS security protocols (SPF, DKIM, DMARC) for domain authentication

Configured S/MIME encryption for support communications with sensitive information

Enabled Multi-Factor Authentication (MFA) for optional employee email accounts

Deployed Sophos Email Security for advanced threat protection

Established Veeam backup for Exchange with automated daily snapshots

Conducted security training and certification focused on client data protection and phishing awareness

Dual-Path Architecture: Business emails via Exchange, customer notifications via SendGrid API

SendGrid Integration: Dedicated IPs with proper warming schedule and domain reputation monitoring

Exchange Optimization: Removed bulk notifications, and instead focused on team collaboration

Barracuda Configuration: Custom rules for hosting industry threats and false positive reduction

DNS Authentication: Complete SPF/DKIM/DMARC implementation protecting domain reputation

Encryption Standards: S/MIME for support tickets containing passwords and server access details

Access Protection: Microsoft Authenticator MFA preventing unauthorized account access

Backup System: Hourly Exchange backups with 30-day retention and 15-minute recovery capability

Improved Customer Email Delivery to 99.2%

Eliminated notification delivery failures
Removed from All Blacklists

Clean sender reputation across major ISPs
Reduced Support Response Time by 40%

Legit emails no longer blocked by customer spam filters
Prevented Email-Based Breaches

Zero successful phishing attacks in 14 months post-implementation
Enhanced Customer Trust

Encrypted communications for sensitive server credentials
Maintained 99.9% Email Uptime

Robust backup system with instant recovery capability
Scaled to 50,000+ Daily Emails

Infrastructure supports business growth without performance degradation