QSettings rewriting the .ini file, so not able to restore the values

[DURGAPRASAD NEELAM]

There is something wrong with my Environment I think, It's working as expected on another SLES machine, sorry for that and thanks for the effort.

[ChrisW67]

Another possibility is that your code constructs two Window objects (deliberately or not), one is actively used, the other is dormant so keeps the originally loaded list, and the last one to be destroyed wins. Stick a breakpoint/qDebug() in the destructor to see how many objects of this class are destroyed as you leave the program.