The trailhead: Importing Data - Challenge keeps failing - see error message

There was an unhandled exception. Please reference ID: KMOEAQSC. Error: Faraday::ClientError. Message: INVALID_FIELD: SELECT Name, Id from Contact where Email LIKE '%example.com' ^ ERROR at Row:1:Column:36 encrypted field 'Email' cannot be filtered in a query call

I have disabled encryption and un-encrypted the "email" fields.  

How can I get around this error?  Or should I just spin up a new Dev Org?

Is it possible to filter out only contact related to an account in a case object. When a case is created from account, it has the account field in case populated with the account name/Id. I want to select contact and the lookup should only show contacts related to this account. Is this possible?
I have a filter criteria case: Account Name ID Equals Contact Name : Account Name : Account ID. Event then it is not working.

Hi,

 

I am accessing the salesforce account as Admin.Now i want to crete a User who should have a field "customer_key" along with  the fields mentioned in Salesforce.com to create a User.

 Inorder to make the custom field available in Salesforce.com  create user page, the custom field need to be added to the existing User object.Is my guess correct?

Also anyone please suggest me on how to add a "Custom Field" to the existing Object in Salesforce.com.

 

 

Thanks