The solution....!
Well I gave up and did a complete new installation of WinXP Home usig the post SP1 disk
Still the IR port would not work, only showing contact with my Nokia 6310i after about five minutes of line of sight contact.
I installed the Nokia driver to no avail, but then reinstalled a wonderful little piece of freeware that I was put onto by Motorola to create a virtual port on com5 for the IR. (You would have thought that Nokia would have been aware of Win XP having no default port for IR hardware) I'll get back to you with the link for this.
Anyware with this program installed everything burst into life and I was able to install the 6310 driver after a bit of fuss. (Nokia instructions gave no valid file paths.)
Anyway, happy buzzing, frewheeling lappy back on line after three days of frenzied button pushing.
BB