When trying to connect to Azure Data Lake using the Azure Data Lake File Input/Output connector (v2.1.0), you get the following error in Designer.
 

Please provide an access token

• Alteryx Designer
  • Version(s) - All
• Azure Data Lake File Input
  • Version 2.1.0
• Azure Data Lake File Output
  • Version 2.1.0

Defect GDC-1198 is filed for the error "Please provide an access token" when using ADLS File connector version 2.1.0

The same workflow works with v2.0.0 of the connector.
You need to downgrade to connector v2.0.0 to get things working until the defect is resolved.

• Microsoft Azure Data Lake File Input Tool
• Microsoft Azure Data Lake File Output tool
• ADLS connector