Milestone & Key milestone will not save

[nicolesantikko]

Hello - we are having a reported issue where our projects team is unable to select key milestone without it changing the dates and duration on the project task. User is opening up an existing project task, checking key milestone (which also checks milestone). Once they save the record, it wipes out the dates and duration and sets it back as zero. I've read that milestones are zero duration but I'm not exactly sure what that means. Can you really only have a zero duration on these records? Any insight is appreciated. Thanks!

[Uncle Rob]

Would also pay to know difference between milestones and KEY milestones.  You need to think of the scale of layers in a PMO.

Milestones are for a single project context.  If I open ANY project, what are the general milestones within that Project.  Now if you have 50 projects rolling up to a Program / Portfolio manager, which milestones would you roll up to that level (hint:  NOT all of them).  The KEY milestones are pre-configured for higher visibility in Program Management interfaces OOB.

[nicolesantikko]

Thanks! We don't plan to share every task with leadership on the status report, but we were flagging important tasks as milestones and hoping to share those on the status report, however, they are existing actual tasks with a longer duration than zero which is where we ran into this issue. 

So, if I understand correctly, for those tasks we wanted to flag as milestones, we would need to create another task and convert to a key milestone to share that information on the status report and keep flagged as a milestone?

[Uncle Rob]

Yes.  Might help to differentiate here:
Its not those duration tasks that are the milestone.  Its the COMPLETION of those task(s) that is the milestone.