I'm glad that you figured it out and thanks for sharing the solution.

That the old 10.0.10240.0 doesn't work isn't that surprising, this was back in the day with VS2015 and then perhaps some of the libraries came with the compiler.

I'm still perplexed by the fact that it doesn't work out of the box for you, if you don't specify -winsdk VsDevCmd.bat is supposed to select the newest as far as I can tell and for you that would be 10.0.22000.0 and that one certainly works for me. According to posts at the Visual Studio community it's supposed to read that information from the registry: HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Microsoft SDKs\Windows\v10.0 You could take a look there and see which version it points to.

Otto

Ok, I have confused the 12.1 version of SM with 12.3 version, I had both installed. But I still have the problem. Now in 12.3 version, I checked for compatible compilers and choose visual C++ build tools 2019. Than the main VS screen doesn't offer anything new to install. And the component that you show is installed. It is in portuguese but you can get it.

PS: I have reinstalled SM 12.3 to try to fix it, but didn't work.

EDIT: I've uninstalled all VS packages and I started SM again, it prompted me to set the compiler and it, as always, opens the VS installer (VS 2019). I just installed everything SM pre-selected and the problem still happens.

EDIT 2: I found inttypes.h, is at:

C:\Program Files (x86)\Windows Kits\10\Include\10.0.10240.0\ucrt

I added this path with the /I flag in a custom compiler setting:

After that the error changes:

It said that it could not open the file, also in the folders:

C:\Program Files\Wolfram Research\SystemModeler 12.3.1\lib\win64\VS2019

and

C:\Program Files\Wolfram Research\SystemModeler 12.3.1\lib\win64\VS2019\msl\3.2.3

there is no libucrt.lib file.

Does SM need some environmental variables? for itself or for VS2019 tools ? Is there any important stuff that SM requires that should be in the PATH env. var. ?