> For the complete documentation index, see [llms.txt](https://docs.verifone.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.verifone.com/support-uk/p400/errors/sred-not-operational.md).
# SRED Not Operational
The "SRED NOT OPERATIONAL" message means the terminal's security key has expired and the device has stopped processing transactions until a key-renewal software update is applied.
{% hint style="danger" %}
**This is for P400 terminals only.**
{% endhint %}
{% hint style="info" %}
**Use this page when** the terminal displays "SRED NOT OPERATIONAL" and has stopped processing transactions.
{% endhint %}
Keywords
Also called: SRED not operational, security key expired, SRED error, key renewal, PED key. Search terms: SRED, security key, expired, key renewal, KEY update, software update.
## Symptoms
You may see:
* The terminal displays "SRED NOT OPERATIONAL" and won't process transactions.
**Most likely cause:** the security key assigned to the PED during setup has expired.
## Resolution
Update the terminal to the key-renewal software version (`v.35_KEY`). This enables automatic key renewal, so the device refreshes its security key automatically during the maintenance period.
{% hint style="info" %}
* If your P400 is running an older software version, you can apply this update and upgrade the software at the same time.
* If you want to keep the same software version, this will need to be raised as a replacement — [contact Verifone Support](https://my.verifone.com/s/supportbyemail) to log a replacement terminal.
{% endhint %}
Follow these steps to update the terminal:
{% stepper %}
{% step %}
### Log in to Webcom
{% endstep %}
{% step %}
### Navigate to Terminals
Hover over `TMS` and select `Terminals`.
{% endstep %}
{% step %}
### Filter terminals
Use the `Filter` function to locate a terminal. Enter the PTID number and click `Filter`.
{% endstep %}
{% step %}
### Edit the terminal
Click the pencil icon next to the relevant terminal.
{% endstep %}
{% step %}
### Set the configuration download
1. Tick `Download Required`.
2. Set `Software Download` to `Yes`.
3. Set `Config Download` to `Mandatory`.
{% endstep %}
{% step %}
### Set the schedule
Select `Maintenance Window`.
{% hint style="warning" %}
This update will not work for `Next Contact`.
{% endhint %}
{% endstep %}
{% step %}
### Choose the software version
Select version `2.10.0.35_P400_KEY`.
{% endstep %}
{% step %}
### Apply the update
Press `Update` to apply the software update.
{% endstep %}
{% endstepper %}
{% hint style="info" %}
Make sure the terminals are connected to the network, or they won't be able to pull the update during the maintenance window. The terminal will be operational the following morning, once the update has been applied.
{% endhint %}
## Still not working?
{% hint style="info" %}
**Still need help? Contact Verifone Support.**
If the steps above haven't resolved the issue, [contact Verifone Support](https://my.verifone.com/s/supportbyemail). Tell us the troubleshooting steps you've already tried — it helps us get you to the right support faster.
{% endhint %}
---
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