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Invalid key when updating from v16 to v21

I'm getting the invalid key message whenever I register my generated license(v21.1.35) on my Xamarin app. I've tried deleting the obj and bin folder but the issue is still persisting.

1 Reply

JM Jeyaseelan M Syncfusion Team April 24, 2023 10:58 AM UTC

Hi Mulayo,

We suspect that you didn’t register the license key in your application properly.

Syncfusion has introduced the licensing system from the version So, you should register the valid license key in your application to remove the license exception message permanently if you are using Syncfusion evaluation installer or NuGet packages.

Refer to the below KB article to know about which version Syncfusion license key should use in your application.


Please, ensure that all the referenced Syncfusion assemblies\NuGet packages are all on the same version as license key’s version in your project.

Syncfusion license keys are version and platform-specific and the generated license key is just a string that needs to be registered before any Syncfusion control is initiated.

To know about generating the license key,


To know about registering the license key,


Refer the below knowledge base article for more information,


If the reported issue is still not resolved,  please share with us the following details to check issue from our side, 

  1. List of Syncfusion NuGet packages\assemblies used and its version,

  1. Screenshot of license key registered place in your application

  1. Target Framework and Platform of your application.
  2. Screenshot of issue you’re facing.


Jeyaseelan M

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