Calendar Corruption???

Check the type of tasks. If it is resource-driven, P6 ignores the task's calendar. In my view, it is P6's calculation error, as the task calendar must always be considered, but you can't do much about it. 

Also, check task constraints and that automatic resource levelling is switched off. 

 

Alex is right about resource-dependent activities, but I would check the hours-per-day conversion first — it produces exactly these symptoms.

P6 stores durations in hours and converts them to days using a factor that, by default, does not come from your calendar. If Admin, Admin Preferences, Time Periods is still sitting on 8h/day while your calendar provides ten working hours, then entering "1d" gives P6 eight hours, and eight hours from 07:00 finishes at 15:00 rather than 17:00. Accumulate that down a chain and you get the assorted 09:30 and 14:00 boundaries you are seeing.

On that same tab, tick "Use assigned calendar to specify the number of work hours for each time period", then open the calendar itself and confirm its own hours per day and per week read 10 and 60. Be aware this re-expresses existing durations — the stored hours do not change, so something that read 1d at 8h/day will read 0.8d afterwards.

Two other checks. Open the calendar's Work Week and confirm the grid really shows 07:00 to 17:00, with no split shift left over from whatever template it was copied from. And add the Activity Calendar column rather than assuming — anything created before you assigned the calendar will still be sitting on the default global one.

A finish at 00:00 usually means a day with no working hours defined at all.

Thanks guys, I appreciate the input. My reason for posting is that I've been using every iteration of Primavera since P3 back in 2002. Each project I develop is set up the same way and each calendar is set up firstly defining the working hours each day, (normally 7am to 5pm Monday to Thursday and 7am to 3.30pm on Fridays). Bank Holidays are then excluded depending on whether the project is in Ireland, the UK or in Europe, along with Christmas Holiday's etc. Activities are set up as Task Dependent, Physical % Complete and Fixed Duration & Units, all as they should be. . . . . I suppose my question is could the system itself be corrupt or could one of the calendars be corrupt and be affecting the others. There are hundreds of programs in my database so deleting all calendars and reinstating them to each schedule would be a massive task. . . . . . 

Genuine calendar corruption is rarer than it looks. Two structural things produce corruption-like symptoms across a whole database.

First, global calendars are shared. If a global calendar was edited at some point, every programme referencing it inherits the change silently. Add the Activity Calendar column on an affected programme and check whether those activities sit on a global or a project calendar. Copying the global into each project as a project calendar isolates them from future edits.

Second, the hours-per-day conversion I mentioned sits at the preferences level, not inside the programme, so a single setting skews times across hundreds of programmes at once — which reads as "the system is corrupt" when it is one field.

A quick way to separate settings from data: export one affected programme to XER and import it into a clean sandbox database. XER rebuilds calendars on import, so if the times behave there, your data is fine and the shared environment is the culprit. No need to delete and rebuild calendars wholesale.

Out of interest — are the affected activities on global or project calendars?

Again, thanks for the insight. . . . This is the baffling thing, the errors are showing up on both Global and Project Calendars. . . .