No it's XP SP2. Unfortunately mine is one of not insignificant number of PCs where installing SP3 renders the machine completely unbootable. It won't even boot into safe mode and the original XP disc's repair utility reports that it cannot repair the installation.
That presents a problem. The software hasn't been compatible with SP2 for many years.
You are going to have to try another brand of software perhaps.
Just for the record, I am going to mark this as answered as the original problem was solved.
I shall raise the XP issue in a new thread as that is a separate problem.
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