Problem with Sandisk 512 cf card in Sandisk Dual card reader sddr-75

Hi,
This is a reply to previous poster (couldn't respond to his message.)
He had trouble with a new sandisk 512 compact flash card in his
Sandisk Imagemate dual card reader # SDDR-75. IT ALSO HAPPENED TO ME!

I just bought a 512 compact flash card. I've been using the SDDR-75
Sandisk dual card reader for a few years with a 256 simpletech card
with absolutely no problems.

I put the new 512 card in my Canon A70, format it, and shoot away. No
problem. I put the card in the reader, no problem. I try to copy the
files.... It hangs the computer. I try again - it copies some, and
corrupts some of the files on the card. (This is on Win 2000.) I view
the card on the camera - some photos will not display.

I reformat the card, reshoot, reboot the computer, then try again.
Same deal.

So, I call Sandisk, give the tech support dude the model numbers. His
reply? "Oh, yeah, that card reader is one of our early models. Your
new memory card is likely pretty new. (I didn't have it with me.)
You'll probably need to buy a new card reader." I ask "Have the
Compact flash standards changed?" "Um, no, but you know technology.
Yesterdays best stuff is todays ....."

So, what to do? I'll try downloading from the camera, to see if the
card is ok. I'll probably try a new card anyway. After that, I am not
sure. The card reader is too old to take back.

Does anyone know why an older reader will not read a newer card?
Nothing else has changed in my camera or pc configuration.

Thanks,
Colin