Downloading vids from Droid X - having issues.

[droidx2010]

I have the Dx in USB Mass Storage mode & when i teather my phone to my computer I get a 'Memory Card is missing" message. i get the mesage to insert a memory card to access media share.

I have a 32g memory card on my phone & it's mounted. can somone help me to get this to work?
Also, when I select pc mode, I'm unable to get my vids from the phone but can access my pics to download. Any clues?