Most cyber attacks on small businesses start with an email. In the UK government’s Cyber Security Breaches Survey 2025/26, phishing was the most common attack, reported by 38% of businesses. Yet only 47% of businesses have two-factor authentication in place.
Optinexs reviews and configures Microsoft 365 security for UK businesses, remotely. The aim is simple: if a password is ever stolen, it should be of very little use to an attacker.
What we check and configure
- Multi-factor authentication for every account, including directors and shared admin logins.
- Conditional Access policies on plans that include Microsoft Entra ID P1, such as Microsoft 365 Business Premium, or Security Defaults on other plans.
- Legacy sign-in blocked, so older email protocols cannot be used to get around MFA.
- External auto-forwarding switched off, with alerts for suspicious mailbox rules.
- Admin roles reviewed, so only the right people hold global admin rights.
- Email protection: anti-phishing and anti-spam policies, plus SPF, DKIM and DMARC records for your domain.
- Sharing settings in OneDrive and SharePoint, including old “anyone with the link” shares.
- Leavers and licences, so former staff lose access and you stop paying for unused licences.
- Backup for Microsoft 365 data, because deleted items are only kept for a limited time by default.
How a Microsoft 365 security review works
- Free consultation. Tell us how many users you have, which Microsoft 365 plan you use, and any concerns.
- Review. With your permission, we check your current settings and explain what we find in plain English.
- Fix. We agree the changes with you, then apply them in a planned order so nobody is locked out.
- Keep it checked. Settings drift as people join and leave. We can review them every month as part of our IT support.
Who this is for
Small and medium-sized businesses, law firms and professional services firms, and any organisation that moved to Microsoft 365 without an in-house IT team to look after it.
Frequently asked questions
Will MFA slow my staff down?
Usually not. Approving a sign-in on an authenticator app takes a second, and on suitable plans Conditional Access can reduce prompts on trusted company devices.
Do we need Microsoft 365 Business Premium?
Not always. Security Defaults give a sensible baseline on any plan. Business Premium adds Conditional Access and Microsoft Defender for Office 365 Plan 1. We will tell you honestly whether an upgrade is worth it for your business.
Can this be done remotely?
Yes. Microsoft 365 is managed online, so the review and the changes are carried out remotely, without a site visit.
Get your Microsoft 365 security checked
Book a free consultation and tell us about your setup. You can also email info@optinexs.com.