Expert Digital Forensics for Microsoft 365 Accounts in London
At Corporate Investigations, we provide professional forensic auditing of Microsoft 365 (formerly Office 365) environments. Whether you are a business, legal team or private client, we uncover critical data from emails, file access, logins and Teams activity.
Our UK-based investigators bring over 15 years of experience supporting internal audits, HR investigations, cybersecurity incidents and legal proceedings.
Why You Might Need a Microsoft 365 Forensic Audit
Microsoft 365 is used daily for email, cloud storage and messaging. This makes it a key source of digital evidence. Forensic auditing helps in cases such as:
- Suspected internal data theft or leaks
- Recovering deleted emails or files
- Tracing user activity around an incident
- Investigating unauthorised access attempts
- Employment or legal disputes involving digital conduct
What Our Microsoft 365 Audit Covers
1. Email Forensics
- Recover deleted emails and attachments
- Identify spoofing, forwarding or altered messages
- Analyse timestamps and communication patterns
2. OneDrive & SharePoint Analysis
- Track file access and sharing history
- Review deleted or altered documents
- Detect unauthorised data transfers
3. User Activity & Login Tracking
- Log-in records, IP addresses and device IDs
- Identify suspicious login attempts or abnormal use
- Monitor compliance with policies and GDPR
4. Microsoft Teams Monitoring
- Retrieve chat history, even deleted messages
- Review file sharing and collaboration patterns
- Track activity across Teams and channels
5. Evidence to Court Standard
- All reports are documented with full chain-of-custody
- Evidence collected legally, securely and professionally
Who We Help
- Private Individuals – Recover lost communications or prove account misuse
- HR & Employers – Investigate misconduct or policy breaches
- Solicitors & Legal Teams – Secure digital evidence for legal proceedings
- IT & Security Teams – Support compliance audits and breach analysis
Why Choose Corporate Investigations
- Over 15 years of experience in digital forensics
- Advanced forensic tools not available to the public
- Confidential, discreet and legally compliant service
- Reporting and evidence prepared to court standard
How Our Microsoft 365 Audit Works
- Free 30-Minute Consultation – Understand the issue and access requirements
- Secure Data Collection – Legal, non-invasive acquisition of Microsoft 365 data
- Forensic Review – Deep analysis of emails, logins, and cloud activity
- Court-Ready Reporting – Clear findings with logs and expert insights
- Follow-Up Support – We assist with legal testimony or further investigation
Audit logs’ time frame can be limited due to licensing and subscription levels
1. Microsoft 365 Subscription Level
- Microsoft 365 E5 / Microsoft Purview Audit (Premium):
Retains audit logs for up to 1 year or longer (up to 10 years with add-on licensing). - Microsoft 365 E3 / Standard Subscriptions:
Retains audit logs for 90 days by default. - Basic or Business Plans:
May retain logs for 30 days or less, and have limited auditing features.
2. Audit (Premium) Configuration
- If Microsoft Purview Audit (Premium) is not enabled, even on E5 plans, extended retention won’t apply.
- You must assign audit log retention policies explicitly to store logs longer than 90 days.
3. Service & Log Type
Different services have different retention behaviours:
- Exchange Online (mail activity): Up to 90 days by default.
- Azure AD Sign-ins and Admin Logs: Typically retained for 30 days unless extended.
- Teams & SharePoint Logs: May vary based on workload and subscription.
4. Licensing Gaps or Changes
If you downgrade or lapse on licensing, older data may become inaccessible or purged if outside retention periods.
5. Data Storage Limits
While not always a primary factor, large volumes of audit data may cause storage and performance limitations, prompting organisations to offload logs to SIEM systems or external storage.
Summary of Default Retention Times:
| Plan Type | Default Retention |
|---|---|
| E3 / Standard | 90 days |
| E5 with Audit (Standard) | 90 days |
| E5 with Audit (Premium) | Up to 1 year |
| With 10-Year Audit Log Retention Add-on | Up to 10 years |
If you think you need an audit, we urge you to act as quickly as possible; delay can hamper an investigation
We operate strictly within UK law, including GDPR and the Data Protection Act 2018. All audits are performed with full legal authorisation or data owner consent.
Contact Corporate Investigations – Microsoft 365 Forensics Experts
Need to investigate suspicious activity or recover data within Microsoft 365? Contact Corporate Investigations today for discreet, expert assistance.
📞 Call Now: 0800 334 5440
📍 United Kingdom – Based Specialists – Serving the UK
💬 Book a Free 30-Minute Consultation
All enquiries are confidential. Let us help you uncover the truth within your Microsoft 365 environment.
