C: and D: Drive Vanished! Dissapeared!

[GX1_Man]

What happened prior to all of this? Can you try a system restore to a point before that? This will not fix defective hardware, but it may be enlightening.

[street1 (RIP)]

This may have 'to do' with your DMA settings.

http://www.real-knowledge.com/dma.htm

[lmkj]

Its been a few months since i last used the cd and dvd drives. The only thing i can think that i have done posibly is at some point a few months ago slotted in a 1gb Ram. I was very sure not to have knowcked anything and have chedcked all the connetions. could the new RAM have something to do with it?

I will look at enabling tha DMA if you think this will help although i have no idea what i am doing!

[lmkj]

i have checked the DMA settings according to that link and they are all fine.

Its all very wierd. i cant help thinking there must be a simple solution... but its looking very unlikely!

[lmkj]

I've Done it!!!!!!

After a seious amount of timeon google and somebravery on my part because i had no idea what i was doing i have founda solution to Code 19.

http://support.microsoft.com/default.aspx?scid=kb;EN-US;320553

Method 1: Remove the registry entry
Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.
Note If you had installed multiple CD-writing software products on your computer, you need to uninstall the software products before you remove the registry keys.1. Click Start, and then click Run.
2. In the Open box, type regedit, and then click OK.
3. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE/System/CurrentControlSet/Control/Class/{4d36e965-e325-11ce-bfc1-08002be10318}
4. On the File menu, click Export.
5. In the File name box, type savedkey, and then click Save.
6. Click the REG_MULTI_SZ data type UpperFilters, and then click Delete on the Edit menu. When you are prompted to confirm the deletion, click Yes.

Note If this data type is missing, go to Method 2.
7. Click the REG_MULTI_SZ data type LowerFilters, and then click Delete on the Edit menu. When you are prompted to confirm the deletion, click Yes.
8. Quit Registry Editor, and then restart the computer.

I chose to do the method 1 as i had already done methos 2 and it hadnt worked! its all working fine now.

Thank you all for your help.
kind regards

[Calum]

Well done, glad you got it sorted.