unsure about that one Haydn, but I found the following :-
What operating systems are supported?
Silent Hunter II is supported under Windows 95, Windows 98, and Windows ME. It is not supported under Windows 2000 or Windows XP. SH2 has not been tested thoroughly under either 2000 or XP, and while it seems to work, no support will be offered by us or the publisher for it. Silent Hunter II will not work under Windows NT. back to top ^
more here http://www.ultimation.com/SH2_faq.htm#q9
Aaaah .... soon be fishing www.aa-computerrescue.co.uk