While in the pre-processing phase of the ERP6 to EHP6 upgrade, I logged on to the shadow instance and made adjustments using SPDD.
I got the message Namespace /CRYSTAL/ does not exist when I was trying to reset /CRYSTAL/PERS_VALUE to original. The issue was resolved using SAP notes 1831145 and 1580365. Since the /CRYSTAL/ namespace does not exist, said namespace was created using SE01. Upon creation, make sure that you go to the global setting, and make /CRYSTAL/ namespace modifiable. Now, you should be able reset /CRYSTAL/PERS_VALUE back to original. Regards, Joel