I've been getting freezes and crashes for days now after recently re-installing COD and reading many of the posts discovered that the culprit was a DX10 issue related to the infamous KB2670838 Windows update.
Although I found that removing the update solved the freezes, I was left with a weird graphical anomaly involving a large square of sea around the plane being a different shade blue, the coastline becoming broken and jagged and the sea flooding the land as I flew inland. I know the south is prone to flooding now, but as far as I know this was not the case in 1940!
After reading further into KB2670838 I found that there was a problem with SDK users and this update, which advised that various DX.dlls needed to be updated (see
https://support.microsoft.com/en-us/kb/2670838). They suggested downloading Windows 8 SDK – the latest version of the software development kit. Now, as FSX users like myself well know, that Sim has SDK built in and you need to install it for various tweaks and add-ins – so those .dll's will be on your system if you are an FSX user.
Anyway, long story made short, I installed the Windows 8 SDK, and the weird graphics in COD are gone without removing KB2670838 (the software installs as a stand-alone and doesn't affect FSX's built in SDK).
I realise this isn't going to affect everybody, but I wanted to get it out there as I haven't seen this issue mentioned in any posts that I've read, and to save any hair tearing out for any fellow FSX users!