To install a new theme if you have never used a custom one before follow these instructions.
Before you do anything you must first create a system restore point to ensure that if anything does go wrong it can be fixed by just rolling back your system.
To start you need to first install Vista Glazz which patches your theme files and allows you to have custom themes.
It can be found here
After installation close the installer and find it in your start menu and run it. It will pop up with a security warning but allow it because this will run it as administrator.
When running the program click the computer icon and choose patch files you will need to restart your computer after doing this.
After the restart open Vista Glazz once again and click the colour icon next to the computer and patch them too. You will not need to restart after patching these.
Now you can download and use any custom theme.
To use a custom theme, go to your system drive (usually c drive) and go to the windows folder, find resources, themes.
Now copy the files of the downloaded theme into the theme folder like so.
Copy the content of the downloaded theme, the theme folder and the theme file into C:\windows\resources\themes
Now you can double click the theme file (the file with the coloured icon) and in the pop up box select the theme that you want and click to apply.
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