Compiling won't save VS2019 files

Hi, I’ve got an issue with a warning being generated by UE4 editor in the Output Log when I click “Compile” in the editor.

LogVSAccessor: Warning: Couldn't save all documents

This is resulting in VS2019 not saving changes to cpp/header files when I hit compile in the UE4 editor, so changes aren’t compiled.

Not sure if this matters, but this project is restored from a back-up on a fresh installation of Windows 10. After copying the project to the Unreal Projects directory on my drive, I removed all the intermediate files, let UE rebuild the project when I opened it for the first time, and then refreshed the Visual Studio project. I’ve since restarted VS and UE multiple times in different orders trying to resolve this.

Turns out I just needed to delete the solution and let Unreal regenerate that. I previously thought the solution was a non-intermediate file, but that was definitely the wrong assumption to make. Oh well. Problem is resolved.