Error 0x8050A001

Value: -2142199807 | 0x8050A001 | 2152767489

What does it mean ?

ERR_MP_BADDB_OPEN  
The scanning engine did not load because it could not load the definition database.
Value: 40961 | 0xA001 | 0b1010000000000001

Where does it come from ?

FACILITY_WINDOWS_DEFENDER  
Windows Defender
Value: 80 | 0x050 | 0b01010000

Other Errors for FACILITY_WINDOWS_DEFENDER