Microsoft Office, the software that includes Microsoft Word and PowerPoint, could be breaking of European data rules after collecting data including the content of private emails, according to a report.

Privacy Company, a consultancy working on behalf of the Dutch Ministry of Justice, said it had found large scale collection of personal data through Office, which Microsoft collected without informing users.

Microsoft said it collected data for functional and security purposes. However, the report found that Microsoft collects data including email subject lines and snippets of content.

The tech giant had previously been sending this data out of Europe to data centres in the US, however it had since moved its collection back to Europe in an effort to comply with the General Data Protection Regulation, which are new data laws introduced earlier this year.

Microsoft collected telemetry data, part of normal software monitoring, of users of Word, Excel, PowerPoint and Outlook. However, the data included sentences from Microsoft Word or lines of emails if its automated systems detected certain actions, like using a spell-checker.

Privacy Company, which conducted the investigation, said Microsoft engaged in "large scale and secret processing of data".

The report from the Ministry of Justice said: "Data provided by and about users was being gathered through Windows 10 Enterprise and Microsoft Office and stored in a database in the US in a way that posed major risks to users’ privacy."