Please recommend a gratis Windows tool to perform search and replace operations in the Windows Registry.
I would like to select a Registry key and have the tool perform the search and replace operation on all values stored in that key and its subkeys.
All I need is support for basic ASCII strings for the the search and replace terms. If the tools supports regular expressions or wildcards, that's great, but not required.
Ideally, the tool will show a preview of all the changes it will make before actually making them, but this is not a requirement.
Open-source is preferred, but not required.
The tool must be portable (no installers, please).
Please specify in your answer which version(s) of Windows your recommendation supports.