Sr. Systems Administrator - Office 365 / Exchange

Location: Fairfield, CA, US; typical office environment with prolonged stationary work and frequent computer use.

Salary: $120,000–$140,000 annually.

Company

hirify.global.

What you will do

• Lead administration of Microsoft Exchange on-premises, including DAG configuration, mailbox databases, connectors, transport rules, and hybrid mail flow.
• Oversee Exchange Online and Microsoft 365 messaging services, including Entra Connect, identity synchronization, and coexistence strategies.
• Maintain Proofpoint email security, DLP, TAP, encryption, routing, and mail hygiene solutions.
• Support Teams and Outlook integration, shared mailboxes, mail routing, auditing, message tracing, and forensic analysis.
• Manage eDiscovery, PRA, retention, legal holds, and compliance requirements.
• Lead troubleshooting, upgrades, migrations, modernization initiatives, documentation, and cross-team projects involving security, networking, and identity.

Requirements

• 6+ years of experience in enterprise messaging administration or equivalent.
• Eligibility to work in the United States and successful completion of a CLETS background check.
• Expert proficiency in Microsoft Exchange in on-premises and cloud environments, with deep knowledge of hybrid architecture and troubleshooting.
• Strong proficiency with Microsoft 365 services, including Teams, SharePoint, and Power Platform.
• Expertise in Proofpoint administration and mail hygiene solutions.
• Strong PowerShell automation skills for Exchange and Microsoft 365.
• Understanding of PKI, SMTP, DNS, certificates, encryption, and secure mail flow, including DKIM, DMARC, SPF, MFA, and conditional access.
• Excellent communication, documentation, and technical leadership skills.

Nice to have

• MCSE Messaging certification.
• Microsoft 365 Messaging Administrator certification.
• Security Administrator certification.

Culture & Benefits

• Full-time position in a typical office environment.
• Work includes collaboration with staff, leadership, security, networking, and identity teams.
• Responsibilities include maintaining system documentation, diagrams, standard operating procedures, and knowledge base content.