Post number 7 in this thread will be of interest. Perhaps the problem is OS-related, triggered somehow by the update you did, and is not a problem with the drive itself.
If the problem does end up appearing to be drive-related, as indicated by the presence of similar symptoms when it is connected to different computers, if the drive is formatted in FAT32 and Toby's good suggestion does not resolve the problem you could try connecting it to a Windows computer and running the Chkdsk utility. Post back if you'd like further information about that, indicating which Windows OS is being used. I have found Chkdsk to be very effective in repairing corrupted disk file systems, which may be what is causing the problem.
Regards,
-- Al
If the problem does end up appearing to be drive-related, as indicated by the presence of similar symptoms when it is connected to different computers, if the drive is formatted in FAT32 and Toby's good suggestion does not resolve the problem you could try connecting it to a Windows computer and running the Chkdsk utility. Post back if you'd like further information about that, indicating which Windows OS is being used. I have found Chkdsk to be very effective in repairing corrupted disk file systems, which may be what is causing the problem.
Regards,
-- Al