I am not familiar with CLI installation process, but if I may just add here my situation, maybe it could help someone …
I just installed Cloudflare WARP on my Windows 10 PC yesteday again, no issues, except I forgot I have had the Cloudflare WARP installed long time ago, then removed it for some other reason and disabled it’s created service.
So, I had to turn on/activate the Cloudflare WARP service (using the tool CodeStuffStarter) to make sure I can click on the “switch” button, and it started working immediately.
May I ask, during the installation, where you asked to provide some administrative access or not? (usually it should ask and the user should accept, otherwise I think it could fail somewhere in between)
If using CLI, were you running the CLI in with administrative privileges?