Does anybody have any experience of installing multiple OSs on a single partition? According to the DD 10.0 User Guide, "8.2.3 Installing another Windows on the same partition" (pp 102) it should be possible, by 'protecting' the system folders. I have tried following the (somewhat sketchy IMHO) instructions, with mixed results; With XP (i.e installing a 2nd XP onto a partition that already has an XP installed), the XP install warns of the presence of a C:\Windows folder and offers the choice of overwriting that or installing to a different folder. (I had hoped that this could be avoided and somehow the system folders would be 'hidden' by OSS). Choosing to overwrite does just that, but installing to a different folder (e.g C:\Windows2) works, after a fashion. The second install is (impressively) detected by OSS, and I can boot to it. But the OSs are not as cleanly separated as when installed on different partitions; for example folders created under C: in one install are visible in the other. With Vista (i.e installing a 2nd Vista onto a partition that already has a Vista installed), again the 2nd install detected the first and automatically moved it to C:\windows.old, but this is not auto detected by OSS and I don't know how to force it. The reason I want to do this is I've only one disk and trying to overcome the 4 primary partition limit. Any other ideas for achieving that ?