To save time many organisations clone existing systems. Why not, it helps save time, but the problem is the clone may have a duplicate SID and changing the computer name will not help. There are a few companies including Symantec who offer SID changers as part of their high end products. But why should we purchase such products for the SID change feature.
But Microsoft offer a free tool called NewSID. NewSID is a program developed by Microsoft to change a computers SID. It will first generate a random SID for the computer and then will proceed to update instances of the existing computer SID it finds in the Registry and in file security descriptors, replacing occurrences with the new SID.
It’s a useful tool which has helped getting rid of duplicate SIDS easily.
For more details about SID, click here