Most likely the X250 device requires a software update to 18.104.22.168 to resolve this issue. Please contact firstname.lastname@example.org for the update link.
In some rare cases the Malware Scanner on X250 shows this error when the DAT file was previously downloaded incorrectly. In this case the workaround would be:
NOTE: You are required to end the AVmallwarescanner process in task manager in order to complete the following process.
1. click on Files folder from Control Panel
2. open x:\Device-System-Files\MalwareScanner\dats
3. delete all dat files
4. click Settings from Control Panel
5. navigate to Tools - Device Health section
6. click Restore Onboard Apps
7. Select Malware Scanner - click OK
8. click Ok on confirmation message.