This is a free Bulgarian interface for Windows XP, which includes making the entire operating system on Cyrillic. The Bulgarian interface is designed specifically for people who are not proficient in English and prefer their computer to be Bulgarian. This will avoid a lot of problems with the setup and solution of problems with your computer.
The application is very easy to install. Just run the file and click “install”. Wait a few minutes and your computer will restart. Then you’ll have Windows in Bulgarian.
The necessary file can be downloaded from here