SD card initialization fails randomly !!

my SD card initialization operation fails randomly . .
when i reset, it initializes . . but when i reset again it does not initialize . . .
like this it happens randomly . .

i want to initialize every-time i turn on and make the system robust . .

how can i solve this ??

What SD device are you using? A link to the hardware might help. Posting the code that fails might help too.