Python troubleshooting index#

Start with the symptom you can observe. Preserve the first exception, HTTP status, or browser-console error: it usually identifies the owning layer.

Installation and dependencies

Import errors, interpreter mismatches, and installation checks.

Data preparation

Shape, dtype, identity, embedding, metadata, expression, and graph validation in prepare().

Viewer embedding

Notebook widget display, the app loading, browser-tab reachability, and browser errors.

Server mode

Bind failures, URLs, HTTP responses, remote access, and process lifecycle.

Hooks and events

Viewer IDs, callbacks, event validation, and session-bundle requests.

Performance and memory

Separate preparation time, I/O, browser rendering, and analysis costs.

HPC and remote access

Refused compute nodes, tunnels that reach nothing, and cluster-specific binds.