System.Diagnostics.Process not working under modalpopupextender

Hi,

I have tried to open file using System.Diagnostics.Process(filename) and it was working fine on just regular button click but when i tried to use it on the button click which is inside the modalpopupextender, the file is not opening at all. In fact, everything is executing without no error but file is not opening. It just returns back to the modalpopupextender. Any ideas?

The peice of code I used was

 System.Diagnostics.Process proc = new System.Diagnostics.Process();
                proc.StartInfo.FileName = filepathtemp;
                proc.Start();

Which is working fine on regular button click but not on the button inside modalpopupextender. Any other approach to open file ? Files to be opened are (doc, docx,pdf,xls, rtf etc).

Any help or ideas would be appreciated.