Foundation - 503 Service Unavailable error

Hi @GSPatil.

Are you having issues importing just this one extension or all extensions?  If this is affecting all extensions you probably need to check \ThingworxPlatform\platform-settings.com to ensure the Extension Package Import policy exists?  Here's an example:

{
    "PersistenceProviderPackageConfigs": {
        "MssqlPersistenceProviderPackage": {
            "ConnectionInformation": {
                "driverClass": "com.microsoft.sqlserver.jdbc.SQLServerDriver",
                "jdbcUrl": "jdbc:sqlserver://localhost:1433;databaseName=thingworx;applicationName=Thingworx;",
                "password": "twadmin",
                "username": "twadmin"
            }
        }
    },
    "PlatformSettingsConfig": {
        "LicensingConnectionSettings":{
            "username":"username",
            "password":"password"
        },
        "ExtensionPackageImportPolicy": {
            "allowCSSResources": true,
            "allowEntities": true,
            "allowExtensibleEntities": true,
            "allowJSONResources": true,
            "allowJarResources": true,
            "allowJavascriptResources": true,
            "allowWebAppResources": true,
            "importEnabled": true
        },
        "ContentTypeSettings": {
            "supportedMediaEntityContentTypes": [
                "image/svg+xml",
                "image/png",
                "image/gif",
                "image/bmp",
                "image/jpeg",
                "application/pdf",
                "image/vnd.microsoft.icon"
            ]
        }
    }
}

I don't have any knowledge indicating that the relational database extension is no longer needed but I will check on it..

Regards.

--Sharon