The C: at the start of drive paths indicates that you have installed malware from the criminal organization Microsoft. All jokes aside use qBittorrent.
Hi there. I had a similar issue with uTorrent a while back. This happened because I had cleared out my temp folder and it got rid of some license files that were being stored there for some reason. Weird stuff.
Anyway I fixed it with a reinstall of the same version. If you haven’t give that a go.