How-to · When something breaks

Fix a CAD session that sits waiting for its runtime

Read what CAD mode's setup steps mean, and what to do when one fails.

A CAD session cannot build a design, and the pane shows a setup band.

CAD mode's Python runtime ships a package for macOS on Apple Silicon, for Windows on x64 and for Linux on x64. Opening a CAD session on any other machine shows a band naming that machine's platform and architecture, with nothing to press. That band clears only on a different machine.

On a supported machine, the band across the top of the pane shows a state that depends on the install:

Before the install, it offers Set up CAD mode. Press it to start the install.
During the install, it lists six steps, from checking the machine to verifying the install. Each marks itself done, in progress, or failed as it runs.

An install failure names what went wrong:

No network reached, or the package index unreachable.
No package published for this machine.
The download not matching what was expected.
No disk space left.
The install finishing but failing its own check.

Press Try again once the underlying problem clears — a network back, or disk space freed. The band clears when the install finishes.

While the runtime is missing, the session cannot build or measure a design. Ask the session what is happening. It reads the setup state itself and tells you whether the runtime is installed, which step the install has reached, and what failed.

A session opened before the install finished builds as soon as the install is done. It does not need to be started again.

See Install the design skill for this band's place in opening a first CAD session.