How can I get Projucer to forget incorrect exporter associations?

When I first tried the WaveTableSynth tutorial I downloaded the .zip of the Visual Studio project.

When I clicked on the VS2017 exporter it showed me a file requester. It hadn’t done this for the example programs so I assumed it was compatible with an older Visual Studio. For this reason I decided to install Visual Studio 2017.

When I went back to try the “Sve and Open IDE” button I again saw the same file requester. Even after a reboot Projucer couldn’t fund the IDE. This seemed anomalous as it had been able to find VS2019 without me having to search for it through a file requester.

Nevertheless I decided to go through the process but for the first time I tried it I thought I’d export it to VS2019 to find out what happened. The Windows dialogue appeared asking if I wanted to make the association permanent and I chose “no”. I only intended to try this once.

When VS2019 loaded it asked me if I wanted to upgrade the VS2017 project, but satisfied it could be made to work I decided not to so I could open it in the now freshly installed VS2017, the IDE it was written for. So I declined the request to upgrade the project and closed VS2019, hoping to reload the project shortly in VS2017 this time through the Projucer.

I discovered unfortunately that the link to VS2019 is persistent. Projucer no longer asks for a file requester for any version of Visual Studio and always boots into VS2019, even when I choose the VS2017 exporter. Even if I try to add a new exporter for VS2015, which I don’t even have installed, when I choose the VS2015 exporter it still boots into VS2019.

The manual appears to be no help telling me where to find the configuration files on the drive and there seems to be no way to change the file association in the Projucer.

How can I tell the Projucer to link the VS2017 exporter to VS2017 not VS 2019?

This isn’t a setting that is configurable in the Projucer - when you click the save and open in IDE button it just tells Windows to open the .sln file as if you had double-clicked it in the file explorer. You can change the default application for .sln files and this will determine which version of Visual Studio is opened: