I had a user who was suddenly unable to interact with a Microsoft Project file and expect the reliant dates and times to change according to parent changes. In other words, there were project dates (or times) which relied upon previous dates (or times) within the project file. (The project start date is a good example of a potentially relied-upon date.)
We started small but by the end had taken pretty extreme measures to correct the matter. Since I don’t use Project I am somewhat reliant upon the users who do to help me understand how their application is supposed to function.
First I ran a Repair using the Project installer. That completed successfully but made no difference in the user’s ability to propagate dates through the project.
Then I tried removing and re-installing Project. This also did nothing.
Finally I pulled out the big guns and used Revo Uninstaller to completely gut-out Project (Advanced mode; removed all Registry entries; removed all related files). Since Project is remarkably intermangled with Office and Visio, I gutted those as well.
I made sure the machine and all its applications were all up to date, and reinstalled Office (then service pack one), Visio, and Project. Again, I ran all available updates.
And fuck me with a cactus if it didn’t have exactly the same effect: nada.
We had a quick drink and contemplated the problem.
No other user seemed to be effected. This user could move to a common machine and there could make said changes propagate. It has to be this user; it has to be this machine.
Turns out there is a setting which allows you to disable what’s called Auto Scheduling. Once Auto Scheduling was re-enabled (as it is by default) the propagations started working as expected.
You can read the Microsoft knowledge base article here (KB 312379). That should help anyone else solve the problem, and hopefully my colorful description will help you find this solution through your favorite search provider.
Have fun with that.