Subtasks are randomly moved or deleted

I am having issues with dependent subtasks connected to a project randomly inserting into a different project or just disappearing when I add new subtasks to projects or try to make edits to existing projects. When this happens it also changes the assigned number of days to the dependent subtask where it has inserted itself.

Any suggestions as to what is happening and how to fix?

Most likely you have a dependency loop which makes tasks moving forward and forward towards the infinity with every action.

An example of such loop:

[Summary Task]

If you find a way to create Finish-Start dependencies between Task1 and Task2 and Task2 and Summary Task, this will mean that Task1 must finish before Task2 starts, Task2 must finish before Summary Task starts which in turn, as a summary task, must start not later than any of its child tasks, that is, it starts before Task1 starts => the whole schedule moves forward.

We try to prevent such loops but sometimes they crawl in. Please check it.

I can’t figure out if what you suggest is actually the problem. Here is example of what is going on:

(Summary Project 1)
(Task 1)
(Task 2)
(Task 3)
(Summary Project 2)
(Task 1)
(Task 2)
(Task 3)

Let’s say I make a change to Task 2 of Summary Project 2 or add Task 4 to Summary Project 2, it will sometimes insert into Summary Project 1 instead, and also change the start -finish time of Task 1,2 or 3 in Summary Project 1.

I typically have 35-40 different Projects and each project has anywhere from 10 to 30 tasks. When I make changes to a Task or add a new Task and this type of error occurs as described above, it seems totally random as to which Project the new task will insert. As a result I am constantly having to rebuild project timelines.

it will sometimes insert into Summary Project 1 instead

It is very unlikely. I want to see a video showing this case.

and also change the start -finish time of Task 1,2 or 3 in Summary Project 1.

This most likely means that something is wrong in the dependencies between those tasks, like I described above.

I can’t say anything for sure without looking at the actual project. Please share it and describe a simple scenario of reproducing the issue, if possible.

I uploaded zip file video showing issue.

I beg you pardon, where did you upload it?

Apparently did not work first time.

It didn’t work the second time either. It just shows “Uploading:…”. Did you copy the progress indicator by any chance?

If this file is big, I suggest uploading it to Dropbox/Google Drive/any other file sharing platform. This forum is not very well suited for huge files.

Maybe this will work