hi all, my system was working properly. but now each time i run the code i get the problem in connection string (that is obtained from app.config file). i get the error at run time: "System.ArgumentException: Format of the initialization string doesnot conform to specification starting at index 0". my app.config file have the following code lines: At run time i get the error: "Format of the initialization string does not conform to specification starting at index 0." thanks Radhika

Looks like an invalid connection string. See http://www.connectionstrings.com/