# License error: Keysight TAP 9.10 not throwing license error

**URL:** <https://forum.opentap.io/t/license-error-keysight-tap-9-10-not-throwing-license-error/187>\
**Category:** Technical\
**Tags:** ks8400-editor\
**Created:** [January 12, 2021, 9:30am UTC](https://forum.opentap.io/t/license-error-keysight-tap-9-10-not-throwing-license-error/187 "2021-01-12T09:30:24Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![bhat.vindya](https://avatars.discourse-cdn.com/v4/letter/b/848f3c/32.png) [@bhat.vindya](https://forum.opentap.io/u/bhat.vindya)\
**Post date:** [January 12, 2021, 9:30am UTC](https://forum.opentap.io/t/license-error-keysight-tap-9-10-not-throwing-license-error/187/1 "2021-01-12T09:30:24Z")

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We were using Keysight TAP 9.1.3 and recently migrated to Keysight TAP 9.10 using fixed license. In TAP 9.1.3 development environment when we try to call testplan.Open() API where the license has been removed , We notice the following error as part of inner exception “System.ComponentModel.LicenseException: License required: KS8000A or KS8400A”. When the same scenario is repeated under Keysight TAP 9.10 we are unable to reproduce the license issue and also we observe that now the inner exception holds " one or more error occurred".  
Kindly let us know if there is any change need to be updated in our application to get the license issue as previously.

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<div class="post-metadata">

**Author:** ![brennen\_direnzo](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.opentap.io/brennen_direnzo/32/6_2.png) [@brennen\_direnzo](https://forum.opentap.io/u/brennen_direnzo)\
**Post date:** [January 12, 2021, 3:44pm UTC](https://forum.opentap.io/t/license-error-keysight-tap-9-10-not-throwing-license-error/187/2 "2021-01-12T15:44:51Z")

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@kaushik.santhanam do you think you could to see what may have changed/how to check for a missing license now?

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<div class="post-metadata">

**Author:** ![kaushik.santhanam](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.opentap.io/kaushik.santhanam/32/208_2.png) [@kaushik.santhanam](https://forum.opentap.io/u/kaushik.santhanam)\
**Post date:** [January 15, 2021, 8:34am UTC](https://forum.opentap.io/t/license-error-keysight-tap-9-10-not-throwing-license-error/187/3 "2021-01-15T08:34:50Z")

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Hi,

According to an issue filed, there was cleanup done regarding how the exceptions were being displayed.

In 9.1.3, if a license was missing the exception that would be printed was something like this:

```auto
Error: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.ComponentModel.LicenseException: License required: KS8400A or KS8101A
   at PluginCacheProxy.CheckCachedProxy(Type t)
   at Keysight.OpenTap.Plugins.Python.SDK.PythonCliAction..ctor()
   --- End of inner exception stack trace ---
   at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck)
   at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark)
   at System.Activator.CreateInstance(Type type, Boolean nonPublic)
   at System.Activator.CreateInstance(Type type)
   at OpenTap.Cli.CliActionExecutor.Execute()
   at OpenTap.Cli.TapEntry.wrapGoInProcess()
   at OpenTap.Cli.TapEntry.Go()
   --- End of inner exception stack trace ---
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
   at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at tap.Program.Main(String[] args)

```

In 9.3, they are consuming the inner exception and posting a simpler cleaner message:

```auto
Unable to load CLI Action : Details:

```

This is the merge request where the changes were made for this:

> **[Licensing and log minor fixes (!84) · Merge Requests · OpenTAP / OpenTAP](https://gitlab.com/OpenTAP/opentap/-/merge_requests/84/diffs?view=inline#c19f135226ec22770107a035323b3bd015c55944_172_183)**
>
> Two improvements: Now, the LicenseException is caught for ICliAction plugins and a simplified log message is written out without a stacktrace, because we know exactly what...

Could you let us know what is the full message you are getting now?