My setup uses 4 monitors, I have 3 in Nvidia Surround state always on a rig and 1 monitor alone on my desk. It had worked just find switching between the 1 monitor and the surround monitors with a macro for months but Then I had to switch out one of the surround monitors due to a defect and got the exact same one. I rebuilt the surround and also re-saved and eventually remade the profile to switch between. Now even after a reinstall i still get this error before. I cant figure out what use to work now no longer works. The reinstall had saved my profiles though but I even tried making a new profile.

An error has occurred while applying your new Monitor configuration.
Please check your settings and try again.
Error: Failed to call SetDisplayConfig. [HR: 31]
[System.Exception]

EDIT: I forgot to mention I can manually enable the surround monitors through display fusion but not through selecting the profile.

I would want it to be clear the 3 monitors are always in surround i never switch out of them. All i am doing is switching them off to have only my 4th monitor on and vice versa.

Edit to add: for manual I just hit enable once for all 3 to come on and disable on old. I feel the automatic should still work.

Did not see a way to do a dm but hope it is okay I attached it to my post. Not sure if it maters but I have reinstalled displayfusion once since the issue began so not sure if it will show anything for when it worked.

I know its been a few days but also wanted to add when I do the quick key switch that does monitors and audio I see the screens come on properly but then errors and switches back.

When I first downgraded and deleted the profiles it gave the error the first time I attempted to switch to the surround monitors. After the first attempt though I have been able to switch back and forth with no error so far. I have not tested after the monitors go back to sleep if the issue persists again or not. If that happens I will respond with more info sometime later today otherwise no news is good news unless you would like more info in help of development.

Well nevermind it is no longer working again. The triples turn on and everything looks good but then it errors out and once I click okay on the error it reverts back to the 4th monitor. This seems to be mainly an issue when using the hotkey as I can switch to the monitors manually after receiving the error once using displayfusion. I am curious if this may have something to do with the desktop wallpaper profile or something with the profiles even deleting them and bring them back maybe it still sees my older monitor that went by the same name but different revision. It all seemed to have started when i swapped that monitor out.

Edit: if there were a way I could show my process in a video file maybe?

I couldn't delete the wallpaper profile so I just defaulted it. I didn't have any Icon profiles but defaulted what I could. I would recommend maybe a reset all button or something in the future if possible. I attached screen shots of the steps to see if you see something I do not. Currently to get this to work correctly when I hit enable in step 2 it errors but if I hit it again after it resets it works. This error is whats preventing it working with macros.

2 things that stand out that we have not mentioned is that the refresh rate is not an even 144hz. This is part of the reason I swapped for the new monitor as it didn't sync right with my other 2 with the new firmware (long story). The other thing which is not as noticeable in the screen shot is there 3 monitors only show as 2 highlighted when not selected. This also caused an odd issue where only 2 would display wallpapers sometimes. Also when I defaulted the default wallpaper profile it still remembered 2 of my screens settings when switching to it and I have since defaulted that as well but not convinced its fully reset.

In my opinion this could be caused by the odd refresh rates or possibly an issue that's related to the far left screen on monitor 2. As always I am happy to answer and troubleshoot as much as possible on this.

Further testing it may of been the splits and padding menu causing this. I had reset it and saved a new profile to it and seems to be working so far. The second attempt did error but it seemed it had lost the splits and padding settings which could of been my error during the saving process. If I do not update again tonight then it continued to work.

Edit: welp after not using it for a few hours it is doing it again.

sorry was out of town on work. I tried this and I still get the following error.
"An error has occurred while applying your new Monitor configuration.
Please check your settings and try again.
Error: Failed to call SetDisplayConfig. [HR: 31]
[System.Exception]"

I will continue to check as this gives me some idea's.

Yes they are all connected through display port in a GTX 1080. Exactly how it was before. Sorry for slow response I have been traveling a lot for work.

Okay sounds good. I was wondering though if it may have to do something with the old monitor being 144hz and the new being 143.98hz. Its the same exact monitor just new firmware on it reads it differently like this. As you saw before I tried uninstalling and removing the profiles but is there any chance it could still have data in the registry still? I want to try a clean install of the software if possible just to make sure this isnt because its somehow remembering my old monitor.

Okay will try that when back in town. Also I want to add I do not know why I didn't try this before but if I try to switch profiles to the triples while already on the triples manually configured minus the sound device it gives the error still. I do not believe its the sound device causing it though as I only recently re-added it and was still getting the error before it. I am hoping removing everything and starting fresh may fix it as that is odd it errors when it has nothing to do but switch audio.

It may of been important to note I had the steam version and I believe the first time I uninstalled I only did it through steam. This time I removed it through control panel but had the same issue. Even though the profile paths you provided were missing I believe I may of forgot to close the application before the uninstall. So I closed it out repeated the uninstall and for good measure rebooted my computer before re-installing.

I have tested 3 times now with no issue so far but we have seen this issue repeat itself before after giving time for the monitors to sleep. So although I may be posting this in haste I believe this may of worked. I will post again in the next few days to ensure it still works or sooner if not. otherwise feel free if you want to know any more information to ask.

Edit: So as feared it failed again. I can do everything manually still and yet if I get it all accept 1 think like switching the primary monitor and disabling the single screen is all it has left it still fails to load the profile. Once I do that myself it detects it and is fine but the point of the program for me is to remove the steps and just load the profile I want its so odd I can do this all within display fusion manually but not through a profile load like I use to do.

I can try this when home later but it did use to work with 3 for months before switching out the monitor. For some reason I am thinking it has to do with the odd refresh rate or maybe the newer firmware in my monitors have some weird energy saver mode for when they sleep. Because the error only happens if they had shut off but it pops them on just doesnt switch the profile over.

Late reply but I have solved my issue. After getting a whole new computer so I could get a 3090 in today market at a decent price I still had the issue when starting fresh. So it had to be the monitors so I dug a little deeper and found they had a Eco mode set to low. I had thought I turned this off but maybe that was on my old monitors. Turning this feature off solved my issue. Thanks for all your support but it seems to have not been on your side at all and was just another annoying eco feature on new devices.