Make sure that you have read/write permission on the C:\ProgramData\ioGAS folder. To check, right-mouse click in this folder and select New>Text Document from the pop-up menu. If you cannot save the text document then you will need to change the permissions for your login otherwise ioGAS will keep requesting the connection details each time the program is started.
The ProgramData folder is a hidden folder so if you can’t see it in Windows Explorer go to the Organize> Folder and Search Options menu option. Click on the View tab and under Hidden files and folders make sure that “Show hidden files, folders, and drives” is selected.