# Best practices for NextSeq 500/550 pre run check failures requiring a power cycle

**Note:** A mitigation has been implemented in NCS v4.2 which prevents the consumables from being marked as used if they do remain in the instrument during a power cycle.

For instruments operating on a Control Software version older than v4.2, the workflow still advises to **remove all consumables** prior to power cycling the instrument.

Some pre-run check failures will require a power cycle for resolution. In these instances, **remove the consumables** from the instrument **prior to power cycling**. To remove the consumables prior to power cycling, complete the steps listed below:

1. Navigate to the Home Screen.
2. Select **Manage Instrument**.
3. Select **Unload Consumable**.
4. Remove all Consumables.
5. Perform a Power Cycle.\\\*

* This is best practice for any NextSeq 500/550 instruments (all NextSeq Control Software (NCS) versions) to prevent issues in detecting consumables.

\\\*For further information, search for Knowledge Base article **How to Perform a NextSeq 500/550 Power Cycle.**

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| *For any feedback or questions regarding this article (Illumina Knowledge Article #5855), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000005855%20-%20Instrumentation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


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