cargo: cargo build/run: Infinite Blocking for rand Dependency

Hello,

I’m just getting started with Rust, and unfortunately I appear to have already run into an issue that I can’t seem to find support for. While doing the “Guessing Game” tutorial in the Rust documentation, I ran into a snag while trying to include the “rand” crate in my Cargo.toml file:

[dependencies]

rand = "0.3.0"

When I try to execute cargo build or cargo run, I get the following message, which doesn’t seem to go away no matter how long I wait:

Blocking waiting for file lock on the registry index

I’ve tried starting a new project and just including the dependency for the default “Hello, world!” program, and I run into the same issue. Here are my cargo and rustc versions:

cargo 0.15.0-nightly (298a012 2016-12-20) rustc 1.14.0 (e8a012324 2016-12-16)

Does anyone know what could be causing this? Sorry to be introducing myself to the community this way, but I wasn’t sure what else to do about the issue. Thank you!

(P.S.: Everything seems to run fine without the dependency, as long as I don’t have any references to it in my Rust code.)