when editing the .msi go to the Launch condition section of orca
at this point there usually are quite a few different entries in reference to older version and different products, some checking if a product is already installed leave these and delete an entry that is similar to this this entry:
((MsiNTProductType <> 3 AND MsiNTProductType <> 2) OR (MsiNTProductType = 3 AND SRVA = “1”) OR (MsiNTProductType =2 AND SRVA = “1”)) AND VersionNT64=””
look for one with “NT,NT5 etc…” in its name it usually is the one which is the os dependancy restriction
