micro sdhc card not recognized by computer and makes my clip zip stop working???

   i’m new to mp3 players so please bear with me if i ask very basic questions…

so i copied music to my micro sdhc card and then put the card into my computer to transfer the music…my computer won’t read the card

then i put the 8 gb card into my clip zip and it made the clip zip turn off…and i wasn’t able to turn it back on until i took the card out of it…what gives?

thanks a lot