Why am I getting errors on an xps import on the policy server on duplicate data, even though  I tried to delete the duplicates in the wamui?

Release:
Component: SMPLC

You are always going to get errors on an xps import on the policy server on duplicate data, even if you tried to delete the duplicates in the wamui. 
You can only officially delete duplicates in the policy store using  xpsexplorer, not the wamui.   
Make sure you backup before attempting to delete duplicates in the policy store in xpsexplorer.
The best practice is to restore a policy store before there were duplicates were in the policy store.
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