Replace the
"D:\\SaveImageOutPutFolder"
with a appliciation configuration string:
1) Open your projects Properties in the solution explorer, and double click on "Settings.settings"
2) In the resulting grid, change the Name to "MySetting", and set the Value to "D:\\SaveImageOutPutFolder". Leave Type and Scope as "string" and "User" respectively.
3) Save and close the settings window.
4) To read your setting:
string s = Properties.Settings.Default.MySetting;
5) To write your setting:
Properties.Settings.Default.MySetting = "My new setting value";
Properties.Settings.Default.Save();