# Keysight License required: KS8000A or KS8400A

**URL:** <https://forum.opentap.io/t/keysight-license-required-ks8000a-or-ks8400a/2204>\
**Category:** General\
**Created:** [November 7, 2024, 6:48am UTC](https://forum.opentap.io/t/keysight-license-required-ks8000a-or-ks8400a/2204 "2024-11-07T06:48:12Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![rajanbabu033](https://avatars.discourse-cdn.com/v4/letter/r/90ced4/32.png) [@rajanbabu033](https://forum.opentap.io/u/rajanbabu033)\
**Post date:** [November 7, 2024, 6:48am UTC](https://forum.opentap.io/t/keysight-license-required-ks8000a-or-ks8400a/2204/1 "2024-11-07T06:48:12Z")

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Hi,  
One of the user is getting following error. He is using floating license. It was working till Yesterday and didn’t work today. Kindly help here. We are using KS8400A.

Keysight License required: KS8000A or KS8400A.  
System.AggregateException: One or more errors occurred. —\> Keysight.OpenTap.Licensing.LicenseException: License KS8000A or KS8400A or TAP\_Engine or TAP\_EditorX v2023.1109 could not be checked out. KS8000 cannot be used.  
at Injected\<Keysight.OpenTap.Plugins.LicenseInjector\>.a.a(String A\_0, String A\_1, String A\_2, Int32 A\_3)  
at Keysight.OpenTap.KS8000.LogStamper.DoEnterTestPlanRun()  
at Keysight.OpenTap.KS8000.LogStamper.EnterTestPlanRun(TestPlanRun plan)  
at OpenTap.TestPlan.OpenInternal(TestPlanRun run, Boolean isOpen, List`1 steps) at OpenTap.TestPlan.Open(IEnumerable`1 listeners)  
at System.Threading.Tasks.Task.InnerInvoke()  
at System.Threading.Tasks.Task.Execute()

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**Author:** ![rolf\_madsen](https://avatars.discourse-cdn.com/v4/letter/r/43a26b/32.png) [@rolf\_madsen](https://forum.opentap.io/u/rolf_madsen)\
**Post date:** [November 7, 2024, 1:01pm UTC](https://forum.opentap.io/t/keysight-license-required-ks8000a-or-ks8400a/2204/2 "2024-11-07T13:01:14Z")

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Hi @rajanbabu033,

Since you purchased a license I think there is a more expedient way for you to contact Keysight support. I cannot help you with you specific license. So maybe you could try your local contact or the support portal at [https://support.keysight.com/](https://support.keysight.com/).

That being said,

- Did you update your software recently?
- What is the version inside your license? If you install Lmtools from Flexera Software you should be able to soo.
- Is there any other license related messages in your log file or on your screen? We try to show obvious errors in a user friendly way, this could be: license count exceeded, support version exceeded, …