Can't get cmdstanr (or RTools42) to install properly

Hello, I’ve been trying to get cmdstanr installed for a few days now, and I keep coming up with this error after using install_cmdstan()

Rtools40 was not found but is required to run CmdStan with R version 4.1.1.
Please install Rtools40 and run cmdstanr::check_cmdstan_toolchain().

The trouble is I’ve already installed RTools (RTools42 to be precise), and I’ve tried changing the path a number of ways (in R and directly in the control panel - I’m using Windows) but no matter what there doesn’t seem to be a connection between RTools42 and R.

As the error message says: RTools40 not found, you have installed RTools42 which is not compatible with versions of R < 4.2, you need to install RTools40