Actually i need to create and write into Excel(.xls) file in windows phone 8.1. when i am using tools like EPPlus,DocumentFormat.Openxml ,error is showing like "Additional information: Could not load file or assembly 'System.Drawing, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified. " so can you please suggest me which is the best tool to wp8.1