SPFX Package Error in SharePoint

[Merindiya]

We are getting the below error while trying to deploy SPFX webpart in SharePoint  .We are using SharePoint 2019 On-premise.

When generating the package it does not generate any errors but when I upload it to the App Catalog library it gives me the following errors

There were errors when validating the App manifest.: Xml Validation Exception: 'The 'IsClientSideSolution' attribute is not declared.' on line '1', position '251'., Xml Validation Exception: 'The element 'Properties' in namespace 'http://schemas.microsoft.com/sharepoint/2012/app/manifest'
 has incomplete content. List of possible elements expected: 'StartPage' in namespace 'http://schemas.microsoft.com/sharepoint/2012/app/manifest'.'
 on line '1', position '342'., Xml Validation Exception: 'The element 'App' in namespace 'http://schemas.microsoft.com/sharepoint/2012/app/manifest'
 has incomplete content. List of possible elements expected: 'AppPrincipal' in namespace 'http://schemas.microsoft.com/sharepoint/2012/app/manifest'.'
 on line '1', position '355'.

[#2]

@Merindiya In the root of your project, you will find a file called ".yo-rc.json", can you please past the contents of that?

I am going to guess that the targeted environment for your SPFx solution is not for on-premises. You have to use SPFx 1.4.1 for on-premises 2019.

[#3]

@Beau Cameron 

Apologies for late reply 

{

  "@microsoft/generator-sharepoint": {

    "isCreatingSolution": true,

    "environment": "onprem",

    "version": "1.11.0",

    "libraryName": "process-hierarchy",

    "libraryId": "57db1213-4b82-4694-8ab7-8516a2e11f5a",

    "packageManager": "npm",

    "componentType": "webpart"

  }

}

This is my yo-rc file

[#4]

@merindiya2040 

I had the same issue after installing 'SharePoint Server 2016 Client Components SDK'

https://www.microsoft.com/en-us/download/details.aspx?id=51679

that overrides the appmanifests.xsd file under

C:\Program Files\Common Files\microsoft shared\Web Server Extensions\16\TEMPLATE\XML\appmanifests.xsd

To fix the issue, you can install 'SharePoint Online Client Components SDK'

https://www.microsoft.com/en-us/download/details.aspx?id=42038