# Troubleshooting

Diagnose and resolve common issues encountered during conversion and deployment. Each issue follows the Possible cause / Proposed action pattern.

* [Wizard and startup issues](https://help.qlik.com/en-US/migration/Content/Qv2qsMigration/troubleshooting/wizard-and-startup-issues.htm) — Resolve UI component failures and port conflicts.
* [QlikView Desktop issues](https://help.qlik.com/en-US/migration/Content/Qv2qsMigration/troubleshooting/qlikview-desktop-issues.htm) — Resolve QlikView instance conflicts and PRJ generation timeouts.
* [Qlik Cloud connection issues](https://help.qlik.com/en-US/migration/Content/Qv2qsMigration/troubleshooting/qlik-cloud-connection-issues.htm) — Resolve authentication failures, API key problems, role misconfigurations, and context conflicts.
* [Build and deployment issues](https://help.qlik.com/en-US/migration/Content/Qv2qsMigration/troubleshooting/build-and-deployment-issues.htm) — Resolve cloud build errors and media upload failures.
* [Conversion output issues](https://help.qlik.com/en-US/migration/Content/Qv2qsMigration/troubleshooting/conversion-output-issues.htm) — Resolve placeholder objects, batch failures, unexpected dimensions or measures, and font differences.

## Which log to check first

QV2QS writes to two separate logs. The system log at `%LOCALAPPDATA%\QV2QS\qv2qs.log` is always written, starting from the moment the process launches. The per-run log in the output directory is only created after command-line arguments are parsed and the output folder is initialized.

* If the process crashes or exits before producing output, check the system log. The per-run log does not exist yet.
* If the conversion runs but produces unexpected results, check the per-run log in the `logs/` subfolder of the output directory.
* If a batch run shows failed files with no error details, check the system log for batch-level errors such as missing QlikView Desktop or prerequisite failures.

For a complete guide to log locations, format, and the overlap between the two logs, see [Logging and diagnostics](https://help.qlik.com/en-US/migration/Content/Qv2qsMigration/command-line-interface/logging-and-diagnostics.htm).

## Enabling diagnostic logging

Run the conversion with `--logLevel DEBUG` to record conversion decisions, cloud API calls, engine discovery steps, and object processing details. Debug-level entries appear in both the system log and the per-run log (when available).

## Learn more

* [Logging and diagnostics](https://help.qlik.com/en-US/migration/Content/Qv2qsMigration/command-line-interface/logging-and-diagnostics.htm)
* [Getting started](https://help.qlik.com/en-US/migration/Content/Qv2qsMigration/getting-started/index.htm)
* [Deploying to Qlik Cloud](https://help.qlik.com/en-US/migration/Content/Qv2qsMigration/deploying-to-qlik-cloud/index.htm)
* [Known limitations](https://help.qlik.com/en-US/migration/Content/Qv2qsMigration/known-limitations/index.htm)