Critical Error: [ t_734872000000029031_PIDX] Exception occured while inserting rows Failed to update data.

Critical Error: [ t_734872000000029031_PIDX] Exception occured while inserting rows Failed to update data.

I have a very similar error to this thread :

My app uses a series of stateless forms to update a master form (pretty large but most field lengths have been optimised for character length) and if I attempt to edit the main form it throws this error.
My error reads: [ t_734872000000029031_PIDX] Exception occured while inserting rows
Failed to update data.

2 examples:

FORM = 'Main'

  1. I open the 'Main' view and select EDIT and manually change a look-up field. It fails and deletes the current field value
  2. I try to bulk edit on the single record I want to change. It fails again
  3. [EDIT] Open view in GRID style and alter look-up field. Click 'Save' - Displays 'Saving Records' for ever....doesn't save.
The Main form contains no fields requiring unique entries and no on edit/update deluge script.

The app is already shared with support. Please advise :-)

Mark