Whenever I launch the game, I hear the intro/menu sounds, but there are no visuals. When I Windows+Tab, I see the program is open, but there's just a gray screen. I've reinstalled the game and the GrayFace patch multiple times to no success. Any ideas? Thanks

First, just to be sure. You downloaded the latest Grayface MM6 2.4 patch from this site (He has older sites as well):
https://grayface.github.io/mm/#GrayFace-MM6-Patch

Then have you tried playing with compatibility modes? I would try Win XP SP2 if you haven't.

Additionally in the MM6.ini are the following enabled?: If so, you could try changing BorderlessFullscreen=0 and see if that makes a difference. (If those options aren't there, then the patch likely didn't install properly)

Also does the game launch properly without the Grayface patch installed?

It is also possible to disable Grayface's custom 32bit engine by changing SupportTrueColor=0 and BorderlessFullscreen=0 then use something like dgvoodoo2 instead while keeping all the other fixes. However I would consider that a last resort.

This is where I've been downloading the patch from. I played around with some more last night and the following combination seems to have the game running alright. Some times the videos don't play properly, but I can hear them. I like to get the game running properly on Windows 10, if possible. Seems like this should be possible?

Compatibility mode: XP Service Pack 3
Reduced Color Mode: 16-bit
Disable fullscreen optimizations SupportTrueColor is not in my config file. BorderlessFullscreen is set to 1 The first time I tried, it launched, but the screen would freeze in the character creator. I could still hear the sound and control the game (could go back to the main meu because I heard the music). After reinstalling, I started to get the following error without GrayFace "DDraw->SetDisplayMode() failed" Not sure why I don't have the SupportTrueColor option at all.

Have you enabled direct play on windows 10? It is a legacy component and does not come active and some older games need it.

I checked on this and it was already enabled for me.

I'm able to run MM6 in windows 10 without any extra compatibility changes so it should be possible. It works better though with XP SP2 compatibility mode enabled once the Grayface patch is installed, I find. You shouldn't need to change anything else. And as the Grayface patch adds a 32-bit engine, reducing the color mode isn't great...

Another quick check, are you launching from the .exe directly? Or are you using a shortcut? Shortcut shouldn't change anything, but I have had it point to the wrong .exe on occasion when I have multiple instances of the same game installed. Just did a fresh install to check and it seems that option has to be entered manually to the .ini now. Are you familiar with dgVoodoo2? It may be worth trying it.

I'll go over the install process, just in case you decide to try:
First download dgVoodoo2_76_1.zip from https://github.com/dege-diosg/dgVoodoo2/releases
From the .zip, copy the 3 main files dgVoodoo.conf, dgVoodooCpl.exe and QuickGuide to the main MM6 folder.
From the .zip in the MS\x86 folder, copy the 4 files D3D8.dll, D3D9.dll, D3DImm.dll and DDraw.dll to the main MM6 folder.

Run dgVoodooCpl.exe, Windows will complain but allow it to run anyways.
In the "General" Tab set "scaling mode" to "Stretched, keep aspect ratio"
In the "DirectX" Tab you'll want to eventually disable the "dgVoodoo watermark", but keep it enabled for now to make sure it works.

Edit mm6.ini, add and/or set: Now make sure MM6 is set ONLY to XP SP2/3 compatibility mode and test it! I hope it works out for you.

Ok, I'm posting what I hope to be the final update here:

1. Updated PC to the latest Windows 10 version
2. Uninstalled MM6 via GOG Galaxy
3. Deleted GrayFace files
4. Redownloaded MM6 via GOG Galaxy
5. Redownloaded GrayFace patch via his site

This somehow allowed the game to successfully launch via GOG Galaxy for the first time. I got to the main menu where it froze up on me (I could only make it to this point by launching directly from the .exe before).

6. Enabled Windows XP SP2 combability

This caused the game to seemingly (fingers crossed) run correctly. No more freezes in menu, videos all played correctly, etc. I relaunched the game multiple times, clicked every option, etc. trying to "break" the game and it seems stable now! Old PC games can be fun haha... thanks for the help! Maybe this thread can assist with someone in the future as well.

Thanks :)

EDIT: The issues came back unfortunately, but they seem to be gone again. The issue seems to be the "BorderlessFullscreen" option that the GrayFace patch adds. Maybe it's because my monitor is above 1080p? Anyway, setting this option to 0 forces it into Fullscreen and it plays fine.

Yeah, that is right! This is one of those games that has issues if you are playing on one of those super widescreen monitors that are over 1080p. One thing that might help is setting you monitor to 1080p setting.

Glad it works for you now! It's always frustrating when an old game gives one trouble.

A couple more points.
I don't know if you looked at it as well, but there exists a very functional mouselook mode for MM6 with the Grayface patch. Download the .ini from his website and add the contents to the end of the mm6.ini if you want to try it for a more modern control feel.

Also if you want looping music, in the mm6.ini the following should be changed: With some computers (mine is one) the .mp3 audio files will also need to be converted to .wav, using a program like freac.

I did download that .ini and the mouselook works great! I've never played these games before and I don't think I could do it without mouselook. Anyway, played for 8 hours straight (lol) today and the experience was fantastic! My music seemed fine, but I've never played the games before so no reference point here.

I have Might and Magic on cd from before gog.com
The music tracks were set up to be able to play just like if you put a cd into a cd player for music.
That means you could take the music with you!
Just pop the game cd into a music cd player and the music would play exactly like a music cd.

Just to bump for the very self explanatory subject: I had the same issue and as the OP stated, it has to do with borderless fullscreen. Which, somehow, requires administrator access to be working correctly.

There are two options: either change the .ini file, or press F4 to switch to fullscreen.

Thanks all for your attention, you may continue with your lives.

I have tried patch now, Windows 10, Nvidia gpu and game is working but, videos as intro, death animation are not visible with patch - just sound only.. without patch all is ok.
Im not using any OS specific setttings..