This happens everytime to me when I insert a new media card. I tried 5 brand new SanDisk SD cards. My BlackBerry tells me to format the media card and then a message pops up saying; "The media card you inserted contains errors".
After that, I repair it and format the media cards on my PC (Windows). The error message still pops up! It doesn't matter where I repair or format it, the problem just persists.