I try Project "Set-up Salesforce Knowledge >Manage Cases Using Articles". 
but, I got the error message as below.
help me.


We can't verify that email-to-case was enabled.

https://trailhead.salesforce.com/projects/import-and-export-with-data-management-tools/steps/use-the-data-import-wizard
Import and Export with Data Management Tools
Use the Data Import Wizard 


I traced the project to the trail head. However, the following error occurred.



I made the lead according to the procedure and transformed the CSV file properly, but I do not know why I get an error.

Help me.

I try Project "Set-up Salesforce Knowledge >Manage Cases Using Articles". 
but, I got the error message as below.
help me.


We can't verify that email-to-case was enabled.

https://trailhead.salesforce.com/projects/import-and-export-with-data-management-tools/steps/use-the-data-import-wizard
Import and Export with Data Management Tools
Use the Data Import Wizard 


I traced the project to the trail head. However, the following error occurred.



I made the lead according to the procedure and transformed the CSV file properly, but I do not know why I get an error.

Help me.