This is getting back to the question about Windows 8.1....what's it doing to folder's/files that try to change/add things in the "Programs (x86)" folder? I still think you need to have the game installed in something other than the Programs (x86) folder. It would seem even running as the "Administrator" the OS isn't adding the Saved .mis files correctly.
You could try one other thing.
Right click on your desktop. I'm guessing Win 8.1 still allows you to create a "New Folder" on your desktop. Create the folder naming it "Game Missions". Open your ME, then open the "Normal" mission you've already created. Save this mission (as I've stated earlier, use the
Save (normal mission) as.... heading) into the "Game Missions" folder on your desktop. Close out the ME. You should see two files in the desktop "Game Missions" folder.....one xxx.mis file, one xxx.tsr file. Now, open the Silent Hunter Wolves of the Pacific/Data/SingleMissions folder, and create a new folder within it, using the same name as the .mis file you just saved. Copy/paste the two files from the desktop "Game Missions" folder into the newly created folder in the games SingleMissions folder.
Are they there? Or, did the OS refuse to allow the copy/paste?
If your game's SingleMissions folder list's your mission as expected, start the game to see if it shows in the list of "Quick Missions" found on the main game's menu page. If so, start the mission to see if that's what you made?
If not......remove the game from the Programs (x86) folder. Open the Registry and remove any remnants as described
HERE, and do a complete re install. Directing the path of installation to a new folder like C:/
My Games. Before starting your newly installed game, add the 1.4 patch to your game. Delete any old shortcut's you may have on your desktop (the .exe/app shortcut to start the game; the shortcut you may have made to open the Mission Editor)....make new ones from the new main game folder.
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A Google search can help explain WHY you
should not put games into the Programs or Programs (x86) folders.
Here's one of the search results: