Relevant version: 6.0
If this issue occurs, perform the following steps:
1. Edit the following file:
2. Edit the following property:
<set-property property="defaultCondition" value="incident.date|date-all|"/>
Restart the Manager service, then try to login again.
You will need to find and delete the corrupt incident (it will be from 'today') and then reset the value back to date-all.