Exception System.NullReferenceException, Message: Object reference not set to an instance of an object means that you are using default host header of Sitecore instead of host header of your SXA site.

To solve your problem:

1. Browse using your SXA Host Header Url.
2. Check that Solr Cores sitecore_sxa_matser_index and sitecore_sxa_web_index exist. If they don't, create them using the following Command: solr create_core -c new_core -d basic_configs
3. Populate schema and rebuild index.

Exception System.NullReferenceException, Message: Object reference not set to an instance of an object means that you are using default host header of Sitecore instead of host header of your SXA site.

To solve your problem:

1. Browse using your SXA Host Header Url.
2. Check that Solr Cores sitecore_sxa_master_index and sitecore_sxa_web_index exist.

If they don't, create them using the following command:

solr create_core -c new_core -d basic_configs 

3. Populate schema and rebuild index.

Exception: System.NullReferenceException Message: Object reference not set to an instance of an object

This error mean you use default host header of site core instead of host header pf your sxa site To solve your problem:

1. Browse using your SXA Host Header Url.
2. Check Solr Cores exist sitecore_sxa_matser_index,; sitecore_sxa_web_index. If not exist create them using the following Command: solr create_core -c new_core -d basic_configs
3. Polulate schema and rebuild index.

Exception System.NullReferenceException, Message: Object reference not set to an instance of an object means that you are using default host header of Sitecore instead of host header of your SXA site.

To solve your problem:

1. Browse using your SXA Host Header Url.
2. Check that Solr Cores sitecore_sxa_matser_index and sitecore_sxa_web_index exist. If they don't, create them using the following Command: solr create_core -c new_core -d basic_configs
3. Populate schema and rebuild index.