Microsoft 365 Support —
Westchester, NY
From initial setup and migration to daily administration and security hardening — Corstar manages Microsoft 365 for Westchester businesses so your team can focus on work, not tech issues.
Microsoft 365 Migrations — Zero Downtime
Moving to Microsoft 365 is one of the highest-value IT projects a Westchester business can undertake. Done well, it improves collaboration, strengthens security, and eliminates on-premises mail servers. Done poorly, it causes email loss, downtime, and employee frustration.
Corstar has migrated multiple Westchester businesses to Microsoft 365 — from Google Workspace, on-premises Exchange, and legacy hosted email platforms. We plan every migration carefully, run it during off-hours, and ensure no data is lost and no employee is left confused on Monday morning.
What We Migrate
- Email — all mailboxes, folders, and historical data
- Calendars and contacts
- File shares → SharePoint and OneDrive
- On-premises Exchange → Exchange Online
- Google Workspace → Microsoft 365
- Shared drives and department folders → SharePoint
- Distribution lists and shared mailboxes
Microsoft 365 Support & Administration
After migration, your Microsoft 365 environment needs active management. Licenses change. Security policies need tuning. New employees need onboarding. Old accounts need to be locked down. Corstar handles all of it.
User Management
Add, remove, and modify user accounts and licenses. Properly offboard departing employees and onboard new hires — same day.
Security & Compliance
Conditional access policies, MFA enforcement, Defender for Business configuration, and data loss prevention (DLP) rules.
Exchange Online
Shared mailboxes, distribution lists, mail flow rules, anti-spam configuration, and email archive management.
Teams & SharePoint
Teams structure, channels, meeting policies, SharePoint sites, permissions, and OneDrive configuration for your organization.
Device Management (Intune)
Enroll and manage company devices through Microsoft Intune — push policies, enforce encryption, and remote-wipe lost devices.
Licensing Optimization
Right-size your M365 licenses. Many businesses overpay for unused licenses or under-license high-value features. We audit and optimize.
Microsoft 365 Security — Beyond the Defaults
Microsoft 365's default settings are not secure enough for most businesses. Out of the box, MFA is disabled, legacy authentication protocols remain active, and many security features are not turned on. Attackers know this.
Corstar hardens every Microsoft 365 tenant against the most common attack vectors — business email compromise, credential stuffing, phishing, and data exfiltration.
M365 Security Hardening Includes
- Multi-factor authentication for all users
- Conditional access policies — block legacy auth
- Microsoft Defender for Business / Defender for Office 365
- Safe Links and Safe Attachments (anti-phishing)
- External sharing controls for SharePoint and OneDrive
- Audit logging and alert policies
- Privileged Identity Management for admin accounts
Microsoft 365 Support — FAQs
Need Microsoft 365 Support in Westchester?
Whether you need a migration, a security audit, or ongoing administration — our Microsoft-certified team is ready to help.