This is the original sql of the view
SELECT TOP 100 PERCENT dbo.tblComputers.Computername AS Computer, dbo.tblComputers.Username, dbo.tblComputers.Domain,
dbo.tblComputers.Firstseen AS [First seen], dbo.tblComputers.Lastseen AS [Last seen],
CAST(dbo.tblComputers.Lastseen - dbo.tblComputers.Firstseen AS bigint) AS [days alive]
FROM dbo.tblComputers LEFT OUTER JOIN
dbo.tblOperatingsystem ON dbo.tblComputers.Computername = dbo.tblOperatingsystem.Computername
WHERE (dbo.tblOperatingsystem.Computername IS NULL)
ORDER BY dbo.tblComputers.Domain, CAST(dbo.tblComputers.Lastseen - dbo.tblComputers.Firstseen AS bigint) DESC
If you want to do "order by" in a view you need the "SELECT TOP 100 PERCENT"