Install the CCCP (Combined Community Codec Pack). It solved every DDERR GENERIC error I had.

I contacted GoG.com support and they are recommending this CCCP codec pack. I was hesitant to try this but since GoG.com support recommends it too, I'm going to try this tonight.

I installed CCCP. Didn't work. I reloaded directX June 2010 and Direct X installer. Reloaded the latest video drivers. Still didn't work so finally I installed the Xvid driver and zipped movies. I didn't get the DDERR error any more but it played the sound from the Seirra movie but only displayed the "loading senarios" graphic. Also rebooted once or twice during all that.

I had one more thing to try. I installed the game in the root of C:\ or C:\SWAT3. I did not use the Xvid files. The game started to work after that. In order to find out what I did to fix it I uninstalled the game. Reinstalled it normally thinking it would prove installing it in root fixed it. It worked anyway. I uninstalled Xvid and CCCP. It continues to work.

I was hoping to post a useful procedure that would show how to install the game. The best I can say now it if the avi movies will not open with windows media player then you'll need to fix that before the game will work.

Don't give up.

It's generally a good idea never to install games to the Program Files folders anyway.

True. I have a C:\Games folder that I always install to.

I have tried my darnest to try and get the error to disappear, from installing to different directories and drives, using xvid codec and movies, using CCCP, using the 2010 June directX redist, compatibility, with Last Resort and without. All together or separate as well.

There's just not fixing my issue it seems, I am running Windows 10 Pro on 64-bit.

Edit: holy heck all I needed to do was install CCCP in 32-bit instead GOD