Which operating system are you using?
Other than upgrading to photoshop elements 12, you could use the adobe dng converter 8.6 to convert the files to dng copies, which pse 10 should then open.
windows
Adobe - Adobe Camera Raw and DNG Converter : For Windows : Adobe DNG Converter 8.6
mac
Adobe - Adobe Camera Raw and DNG Converter : For Macintosh : Adobe DNG Converter 8.6
how to use the dng converter