---
title: "Troubleshoot CAT"
description: "What went wrong and where to find out — the log of each tool, how to turn it up, and the symptoms that have one usual cause"
url: "https://docs.justcat.it/how-to-guides/licensing-and-admin/troubleshooting/"
---
# Troubleshoot CAT


## Read the log

CAT can fail at any point — reading the project file, loading a list of tests from a database, connecting to a data source, running a query, writing an output — and the log says which, in order, with the error the provider returned. It is the first place to look.

| Tool | Where the log is | Turn it up |
|---|---|---|
| **CAT Studio** | the **Logs** page in the left bar | — (always on) |
| **CAT CLI** | the console, and `Documents\CAT\Logs\cat-log.log`; off by default | `-l Information`, or `-l Debug` |
| **PowerShell module** | the console, and `Logs\` next to the project file (`Documents\CAT\Logs\` before a project is open); `Information` by default | `-LoggingLevel Debug` on `Invoke-CatProject` / `Open-CatProject` |
| **Python module** | standard output, and `Documents\CAT\Logs\` (`./CAT/Logs/` on Linux) | `logging_level=cat.LoggingLevel.DEBUG` on the first call |

In a pipeline or a scheduled task CAT runs under another account — its `Documents\CAT\Logs\` is that account's. The last file is the one you want; in PowerShell:

```powershell
Get-ChildItem "$([Environment]::GetFolderPath('MyDocuments'))\CAT\Logs" | Sort-Object LastWriteTime -Descending | Select-Object -First 1 | Get-Content
```

## The usual suspects

* **A value still has percent signs in it** — `%DWH_CONNECTION_STRING%` reaching the provider as text — the environment variable is not visible to the process: created after the session started, misspelled, or not mapped into the pipeline step. [Use environment variables](https://docs.justcat.it/how-to-guides/organize-and-run-tests/use-environment-variables/ "Use environment variables") has the check.
* **"Unexpected token" on a line of the project file** — a value starting with `%` or `*` that is not in quotes, or wrong indentation; the line number is in the message.
* **The data source works in Studio and not in the pipeline** — a different account: the database login, the license key, the environment variables are all per account. See [Integrations](https://docs.justcat.it/reference/integrations/ "Integrations").
* **A test ends with `Error`, not `Failed`** — the query never ran to a verdict: the provider's message (invalid object, login failed, timeout) is in the test's message and in the log; see [Results](https://docs.justcat.it/reference/tests/results/ "Results").
* **The run is refused before any test** — the sign-in and plan check: no token or key, a plan that does not allow the tool, the output format or the unattended run; every tool names the reason (CAT CLI also with an exit code `2`–`7`). [Compare plans](https://docs.justcat.it/compare-plans/ "Compare plans") · [Apply a license key](https://docs.justcat.it/how-to-guides/licensing-and-admin/apply-license-key/ "Apply a license key").
* **`sets match` fails on rows that look equal** — order: both sets must be sorted the same way, or `Sort data: true`; see [Order and key](https://docs.justcat.it/reference/tests/order-and-key/ "Order and key").

## Still stuck

Use the **Get Help** button on the right of this page, and attach the log — with `Maximum errors logged: 0` on the tests if the log must not carry data.