Opera 10.51 Won’t Open in XP

The Club has a dual-boot setup with XP / Windows 7. A few weeks ago Opera 10.10 would not open in XP, so we upgraded to 10.50 — that seemed OK (slow, but OK).

Today, we started Opera in XP and it wanted to upgrade to 10.51 — why not, we said. Now it will not open.

At home, I found version 10.51 to be better and faster than 10.50, with no obvious bugs.

Any help gratefully received (a Google search just shows that this problem has been fixed).