I have signed for a trail licence and want to investigate SOQL function. When I login into the workbench and select Sandbox it redirects me to test.salesforce.com I enter my Salesforce credentials it cannot authenticate. I have tried chrome and firefox, tried clearing the cookies and cache but no success. Salesforce login works fine
Trial editions of Salesforce are production instances, not sandboxes. Choose Production and use your trial credentials, and you should be able to log in to Workbench.