Indy and Bert,
OK, sometimes bugs are caused by the littlest things. The following problem broke both my ability to add new patients and e-prescribing:
I had (and have had for years) my Windows XP Professional Regional and Language options (in the control panel) to display dates as
08-MAR-2011
rather than the default
03/08/2011 on the affected computer.
(this was because I do international clinical pharmaceutical trials, and the dates must be displayed in that format)
Apparently this was enough to break Amazing Charts e-prescribing and somehow the add new patients page.
I have restored the Windows Date Setting to DD/MM/YYYY.
Things are now working (Except for TSP800 multiple prescription printing and the loss of the Florida Format (where in FLorida we have to say MAR/08/2011 or 08/MAR/2011, but not 03/08/2011- pharmacies do kick back prescriptions if one doesn't write out the month).
Thanks for everyones help.