Someone inside may be taking data
What happened
Ojava saw a combination of signs (protection off, USB storage, many files copied) that fits someone taking data. Talk to the person before drawing conclusions.
How serious
Serious: deal with it today.
Steps: Windows PC
Ask the person at that PC what they were doing at that time (installing something, a link in an email, a USB stick).
Find out who plugged in the USB storage and why. If nobody knows, keep the stick away from other PCs and give it to your IT provider.
Turn protection back on: Start → Windows Security → Virus & threat protection → Manage settings → Real-time protection: On.
How to check it’s fixed
Fixed when the deep scan finds nothing, protection is on again and Ojava shows the PC as healthy for 24 hours.
When to call your IT provider
Call your IT provider today, before using the PC again for work.