Some of readers reported this problem in windows theme, as whenever they change theme in windows 7 under personalization section. If you have ever changed windows 7 theme you would know when you open personalization and appearance section, you will theme with a name Unsaved theme as you can see in the image below.
Now if you are one of those windows users who see this and would like delete this unsaved theme. The most easiest way to get rid of this is by naming this unsaved theme in windows you can easily get rid of this, for this you will need right click on this theme and then save the theme by giving it a name as shown in the image below.
Once you do this, the unsaved theme will be gone until next time you change the theme or change any thing related to current theme applied in windows 7. In case if the above solution does not solve your problem and you still see the unsaved theme in windows 7, you should follow the solution by WinHelpOnline at this page – in short this tutorial tells you to delete Custom.theme file. When you do this, you will not see the unsaved theme the next time you open Personalization section in windows as shown in the image below.
Another method which you can try, then follow this procedure. Close personalization click the Start button, type %localAppData%\Microsoft\Windows\Themes in the search box and press Enter. Delete the Custom.theme file. Now, open Personalization again and check if the Unsaved Theme still exists. If so, try deleting and see if it reappears. You can also refer to this technet thread to fix your problem.