On the Magix Music Maker Premium 2015, I had a file saved named '7', and opened a new project which accidentally overwrote the '7' file. I have the new file, but am wondering if I can retrieve the old file that's also called '7'. I'm using Windows Vista. Any help would be greatly appreciated.
If MMM 2015 has saved a backup copy, then you may be able to recover it.
Try File, Backup, Load backup project - backup projects have the .mm_ file extension and should be located in the same folder as the original project file.
If there are no backup projects, then there is no way of recovering the over written file.