SQL Server 2005 Cluster Node Error?

Hi, I am currently building a 3 node cluster running on Windows 2003 Enterprise R2, 64Bit and have hit a snag.
The cluster is built and all looks OK I have node 3 as the passive node.
I have installed a virtual SQL Server on node 1, with node 3 as passive.
Node 1 has 6 disks for which it is the owner O,P,R,S,T,U The system DB files are on O:
I am trying to install another virtual instance on node 2, again with node 3 passive. THis has disks F,G,H,I,J,K During the install I specify that it is to use disk F for the data files. When it gets to the database services install, I get a message that an unexpected error has been encountered erroe 183. And another pop up saying that O: is an Invalid Drive. Nowhere have I specified drive O: as I cant see it anyway as its owned by node 1. I have googled this and cant find anything, I have checked the registry on node 2 and cant find any reference to O:
I am pulling my hair out !! Does anybody have any ideas??
Thanks Ben

Are you sure you have set up shared disks and quorm disks correctly ?
Regards
Sat