When the dependency functionality was introduced to ProjeX some unique way of identifying specific tasks need to be implemented. This is the pointer value for the task which is currently stored in the column of the task sheet labeled P.
Each task (and now group) is given a pointer value once a Gantt chart is generated or one of the various dialogs is brought up that operates on tasks. ProjeX uses the pointer value to identify the properties of the task (eg. is it defined by a start and duration or a start and end).
As said before this number must be unique and must not be altered by the user or the task definitions and dependencies will be corrupted. Problems have occurred in the past where the user has copied tasks or groups of tasks as rows of the Excel sheet and pasted them ending up with two sets of tasks with the same pointer numbers. In this case the user should delete the pasted pointer values so that ProjeX can set up new values for them. E.G.
| Copy our initial block of tasks |
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| Paste them below, we now have duplicate pointer values |
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| Now lets delete the Block2 pointers |
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| Now we can generate the Gantt chart without a problem |
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