Thanks for replying. And fyi, I'm a System Administrator so fear not that I'll delete something that I shouldn't from the Registry. The problem in CCleaner is that using the "Open in Regedit" item on the context menu takes you nowhere. In other words, it appears that these 8 items do not actually exist in the Registry. I did a scan of the Registry using one of my favorite utilities, Registry Crawler, looking for anomalies and the only thing I could find was these 8 items (see screenshot), but they aren't "file extensions" but "default icons", all but 2 belong to IconPackager icons and the remaining two point to the "shimgvw.dll" in WINDOWS, which is used mainly by Windows Picture and Fax Viewer. Other than that, everything looked fine.