Moderator: Intaver Support
When you are first adding the low and high estimates, you must provide a statistical distribution by using the Input Distribution > Duration dialog box.
Once this is done, you can modify the Low and High estimates without using the dialog box. However , this will bypass any error checks that are done when you input the data, for example you cannot enter a low estimate that is greater than the base duration. Looking at your file, I found a few things that could be causing the issues you are seeing. If you are modifying the data without using Duration dialog box, it is possible to enter values in which Low > Base or High < Base or Low which could cause errors.
If you look at the image below, I have indicated a few issues in the data that should be addressed.
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