Easy Registry Optimizer 

Safety: Always back up your registry and restore if registry gets currupted or spy/adware changes registry values. Optimization and fault prevention: Remove invalid registry entries to make Windows and programs run faster and with less errors.
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Registry Workshop 

Registry Workshop is an advanced registry editor. In addition to all the features that you can find in RegEdit and RegEdt32, Registry Workshop adds many powerful features that allow you to work faster and more efficiently with registry related tasks.
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