# Get Serial Number

Gets a software serial number using the O.S. API.

Action available for the following operating systems:

![](/files/-MGIiDGuNcrVFP-DbUma)

### Parameters

* **Target** - The control or variable that saves the terminal serial number.
* **Version** - The version of the serial number to retrieve. See Notes for more information. The possible values for this parameter are:
  * 2.4.0
  * 3.0.0
  * 4.0.0

{% hint style="warning" %}
You should always use 4.0.0 version.
{% endhint %}

{% hint style="info" %}
Version 2.4.0 uses an old API on Windows CE/Mobile and its only listed to preserve compatibility in projects made with earlier Kalipso versions that need to use the serials returned by that API.
{% endhint %}

{% hint style="info" %}
Version 3.0.0 uses an old API on Windows 10 client and its only listed to preserve compatibility in projects made with earlier Kalipso versions that need to use the serials returned by that API.
{% endhint %}

{% hint style="info" %}
In Desktop client if the returned serial starts with "Y-" it means Kalipso was not able to read the serial number from any hardware component, and with more and more security restrictions it is probably due to permissions. You can check if it is a permission problem by making "Run As Administrator" to KClient. If in this case it always works, than it is due to permissions.
{% endhint %}


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