Is there an alternative to DataLoader/DataLoader.io with SFDC professional edition? I need to mass update task information with a field added.

• Contact your Account rep or Salesforce Support to see if they will grant a temporary API license
• SimpleImport (https://appexchange.salesforce.com/results?keywords=simpleimport)
• Excel Connector https://developer.salesforce.com/page/Force.com_Excel_Connector
• Enabler4Excel (https://www.xappex.com (https://www.xappex.com/)) - this one is free trial and then paid, but it is very feature rich compared to others mentioned above.

--Derhyk