Hardrive not accessible?

?About a year ago my windows 98 got another hardrive and it worked fine. Then we decided to install a high speed internet comcast which needed alot of space. So we put all my stuff  onto one drive (D) and the other (C) was used for the internet. When everything was done and the computer started again with the internet on the (C) and the (D) still had the icon but when I double click it has
D:\ is not accessible  A device attached to the system is not functioning
Is  there any way to get the drive working again w/out losing the info already on it? :-/