Left PC connected overnight and in morning found message that Outlook 2003 had had to close.
Rebooted but got same problem on opening Outlook. It started to download a couple of emails, then closed.
I have uninstalled and reinstalled several times. I have created a new profile in Control Panel. Same problem.
PST was large. 2gb+. However, that PST and others I use all open without issue on another PC.
Have tried Run | Outlook /safe. Same problem.
AVG virus check reports system is clean.