Split hard drive,parts disapear then returns later

I have a split my second hard drive into 2 parts.The C Drive which has the Operating System on always remain but my second Drive regularly disappears and any programme on it will not work.Turn the computer off for a while seems to put thing right most times.
Can anybody help me put this problem right please.
Thanks in advance.

 

First, what do you mean when you say that the C: drive is on your second hard drive. What happened to the first hard drive?

Do a virus check.

 

Sorry I didnt explain it very well.What I meant was that My first Hard Drive being the Crive has the Operation system on (XP) and my Second Drive contains the split which are named 157gb and 26gb relating to the size of the partions for the second Drive.So in theory I have 3 different Drives but realy on 2 Hard Drives.

 

make a backup of the 2nd hard drive that 1 that has the 2 partitions and format the hd

 

Thanks I will do that when I have the Time and I will also do a virus check but I have AVG running all the time.
Thanks for know and if things dont go according to plan I will be back
thanks all for the moment