External drive issues Mac to PC
 

I have transferred gigs captured on pc to my mac for editing a fair amount of times, but have been having issues when transferring from Mac to PC for internet upload.
It seems that after I use an external drive Lacie Q4 500 or a 2 gig thumb drive on the mac a few times my internet pc wont see them or may see them but won't copy from I get an I/O error...any ideas ?? and yes when new I formatted them for use on both platforms. I have 5 lacies and a couple WD's and one maxtor and my pc won't see them anymore yet they work fine on the mac.

I honestly dont' know why this is happening. Has it been this way all the time or just recently? Have you changed any drivers an either system?