I get an unexpected Windws shutdown during gameplay. This has happened three times but not at the same place inthe program. Does anyone have any ideas as to what is causing it? I am running win 7 x64 Ultimate.

Have you checked the WC forum? gog.com/forum -> search "wing com" in the bottom left search bar

if that doesn't help, try contacting Support

Unexpected shutdowns pretty much always boil down to hardware issues (e.g. overheating or bad power, excess current, shorts...). The same issues can also cause unexpected restarts.

I don't know how windows handles it but many OSes can restart abruptly if a kernel or driver bug crashes the system too hard for it to even report an error. A stall could also cause a watchdog to reset the system.

It's probably nothing to do with the game.

Have you looked in the Windows event log to see what happened? Do you have Windows configured to hold on a BSOD to show error message or are you set up to straight restart? I'm assuming it's not windows update doing it.

I *think* that WC Prophecy is a dosbox game, so unlikely to be related to the game. My guess would be power supply or dodgy/unseated RAM. Have you physically moved your computer recently?

There's an OpenGL patch for Wing Commander Prophecy that improves the game's performace, appearance and
stability on more modern PCs.

https://www.gog.com/forum/wing_commander_series/wc_prophecy_wont_run_on_windows_10_can_anyone_help_me_out/post2
https://www.gog.com/forum/wing_commander_series/wing_commander_prophecy_opengl_upgrade/post1

Ooh - I was wrong, it's a Windows 95 game. Still think it's unlikely to be causing a shut down on its own - more likely to be associated hardware issues. Typically, I'd expect a game that crashes to just lead to a "programme has stopped responding" or "has caused an error and needs to be closed" dialogue box.