Message 67

Severity:Serious (value = 2)
Default Action:Error (value = 0)
Description:Constraint <name> cannot be conditional unless defining Constraint RHS of period type = "interval".

Message 67 occurs in the following circumstances:

Since Condition objects are evaluated every interval, which is reported as Hours Active, conditional constraints can only be defined as interval-type i.e. by defining the RHS property.