The reports can be cloned and edited to omit tables containing multiple (and different) entries for the same computer or, in the case where VMWare is common a clause can be added to the "Where" statement telling it to discount anything where the device column contains "VMWare%'
WHERE l1.[Device ID] = SUBSTRING(o1.[Install Path],1,2)
AND d.[System Type] = 'Win32'
AND t1.[Device] NOT LIKE 'VMware%'
AND i.[Name] LIKE '%ComputerName%'
AND d.Domain LIKE '%Domain%'
AND it.[Guid] = '%Collection%'
GROUP BY i.[Name], s1.Domain, s1.[Logon Name], t1.[IP Address], t1.[Default Gateway], t1.[Subnet],
s1.[System Type], sn1.[System Manufacturer], sn1.[Computer Model], sn1.[Serial Number],
cpu.Type, cpu.[Speed], m1.[Total Physical Memory]/(1024 * 1024) + 1,
cop.[OS Name], cop.Version, o1.[Service Pack], SUBSTRING(o1.[Install Path],1,2),
l1.[File System], l1.[Size in MBytes], l1.[Free Space in MBytes]
HAVING COUNT(t1.[IP Address]) > 1
ORDER BY i.[Name]
This will eliminate many, but probably not all duplicates, because some computers may have multiple NICs which should be legitimately reported.
Notification Server 6.0.5287, Inventory Solution for Windows 6.1