Rustup not installed at [location] with different CARGO_HOME and RUSTUP_HOME

[juliandevelops]

Verification

• I searched for recent similar issues at https://github.com/rust-lang/rustup/issues?q=is%3Aissue and found no duplicates.
• I am on the latest version of Rustup according to https://github.com/rust-lang/rustup/tags and am still able to reproduce my issue.

Problem

Running rustup update does update the version but ends with error: rustup is not installed at [location of $RUSTUP_HOME].

I did check the RUSTUP_HOME and CARGO_HOME. They are set as follows:

• $RUSTUP_HOME: custom/location/rustup/bin
• $CARGO_HOME: custom/location/cargo/bin

Both are sitting at the same custom/location just with different suffices.

I did check the actual location and the error message is correct. The rustup binary itself is installed at $CARGO_HOME/rustup together with all the other binaries such as cargo, rust-analyzer and more.

In the $RUSTUP_HOME are the installed toolchains, but no binaries.

Steps

1. Install rustup via rust installer (curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh)
2. run rustup update
3. Rustup update works but ends with error

Possible Solution(s)

No response

Notes

No response

Rustup version

rustup 1.29.0 (28d1352db 2026-03-05)
info: This is the version for the rustup toolchain manager, not the rustc compiler.
info: the currently active `rustc` version is `rustc 1.96.0 (ac68faa20 2026-05-25)`

Installed toolchains

Default host: aarch64-apple-darwin
rustup home:  [redacted]

installed toolchains
--------------------
stable-aarch64-apple-darwin (active, default)

active toolchain
----------------
name: stable-aarch64-apple-darwin
active because: it's the default toolchain
installed targets:
  aarch64-apple-darwin

OS version

macOS 26.5.1 on Apple Silicon Chip

[rami3l]

@juliandevelops Hello, thanks for posting this issue.

Per your description I don't see anything wrong with your setup.

In fact, manually overriding RUSTUP_HOME and CARGO_HOME is even the recommended way to test rustup in an isolated environment:

> RUSTUP_HOME=home CARGO_HOME=home target/debug/rustup-init --no-modify-path -y

So the only conclusion that I can come up with is that you are probably running two instances of rustup, or the value of RUSTUP_HOME and CARGO_HOME overrides are not consistent when you installed rustup via rustup-init and when you run it later.

[juliandevelops]

@rami3l thanks for the quick response. I added my file structure below.
I did notice, that cargo/bin does contain symlinks to the rustup/bin/toolchain/[toolchain]/bin, with exception of the Rustup binary which is located at $CARGO_HOME and does not link to rustup - which does explain the error.
I can install rust again from scratch with those two values, but I don't think that's the issue as the location in the error message is correct. The fact is, that rustup is not installed at $RUSTUP_HOME but rather at $CARGO_HOME.

And for me running two rustup instances, I don't think that's happening, I'm not aware of downloading multiple instances.

Does that paint a clearer picture?
Can I provide any more information?

[rami3l]

@juliandevelops Your installation looks pretty standard.

However there is one thing I would like to confirm: when rustup throws error: rustup is not installed at <path> it means it thinks that path doesn't exist (you can see the code here). This can also happen if you have tinkered the FS permissions for example. Try to run which rustup and see where it lands.

Finally, since you are using macOS, the sandboxing mechanism can stop you as well.

Try to see in the terminal if you can ls -lah your $CARGO_HOME/bin and see what output it generates, whether you have typos, etc.

[juliandevelops]

@rami3l I didn't even consider this. That could be a reason.
The output of which rustup points to $CARGO_HOME/rustup not $RUSTUP_HOME/rustup.

ls -lah in $CARGO_HOME provides a normal looking directory (see attached screenshot)

It provides a default owner (me - just as excepted) and a default group of staff.
The permissions do also look normal. rustup is allowed to be executed and also written by myself.

Another thing I did notice: You wrote $CARGO_HOME/bin. The /bin is part of my $CARGO_BIN. Same with $RUSTUP_HOME. Could that be a problem?