The Warning field indicates whether Microsoft Project has identified a potential scheduling conflict with a manually scheduled task's (manually scheduled task: This type of task can be placed anywhere in the schedule without Project rescheduling it; it does not move as related information about the task changes.) start date, finish date, or duration, for example, a problem with a task link (task dependencies: A relationship between two linked tasks; linked by a dependency between their finish and start dates. There are four kinds of task dependencies: Finish-to-start [FS], Start-to-start [SS], Finish-to-finish [FF], and Start-to-finish [SF].) or a date constraint (constraint: A restriction set on the start or finish date of a task. You can specify that a task must start on or finish no later than a particular date. Constraints can be flexible [not tied to a specific date] or inflexible [tied to a specific date].). The information with the potential problem is underlined in red. You can then right-click the field to read the warning or suggestion to improve the project.
Data Type Yes/No field (Yes/No field: A type of field with content set to either Yes or No; also known as a Boolean field or a True/False field. For example, the Recurring field indicates whether the task is a recurring task.)
Entry Type Calculated (calculated field: A field in which the value is determined by Project based on information in other fields. Project may recalculate the value automatically or when you specify, depending on your choice of calculation settings.)
How Calculated When Project detects a potential scheduling conflict with a manually scheduled task, it generates a warning and changes the setting of the Warning field from No to Yes. In its field, the problem data is underlined in red.
Best Uses Add the Warning field to any task sheet when you want to scan for any potential scheduling conflicts among manually scheduled tasks. You can sort, group, or filter tasks to show all tasks with potential problems together and systematically resolve them. To learn the nature of the conflict, right-click the task and click Fix in Task Inspector. The Task Inspector pane appears, which describes the problem and suggests solutions.
Example You have two manually scheduled tasks that are linked with a finish-to-start task dependency. You’ve entered a finish date of May 4 on the predecessor task and a finish date of May 5 on the successor task. You change the finish date of the predecessor task to May 7. Because Project never changes entered dates of manually scheduled tasks, the schedule now shows that the successor task ends on May 5, two days before the end of the predecessor task—an obvious scheduling conflict. A red underline appears below the finish date of the successor task, and the Warning field switches from No to Yes. You right-click the task and click Fix in Task Inspector.
Remarks The red underlines that indicate potential scheduling conflicts in manually scheduled tasks appear until resolved or until you choose to ignore warnings for the tasks. To ignore warnings, change the Ignore Warning field from No to Yes. Or, in the Task Inspector pane for the task, clear the check box labeled Show warning and suggestion indicators for this task.