The Windows Registry contains lots of useful information used by COM stored in a variety of keys. NirSoft's RegDllView is portable freeware that extracts and displays a list of all registered DLL, OCX, and EXE files. It shows lots of data about each file, such as the last time it was registered and all registration entries (CLSID/ProgID). RegDllView not only displays entries but also disables, unregisters, and reregisters them; deletes selected entries; and creates .Reg files for deleted entries. It can also open entries in RegEdit. RegDllView has a customizable view, and it can create and save HTML-based reports.
RegDllView's user interface is plain but well-configured. Businesslike, efficient, and compact, it's divided horizontally between an upper list view with customizable headings and a lower window for displaying selected items. Options include displaying missing files in color and extracting version information; we could also customize the view by adding grid lines, showing tool tips, and marking odd and even rows like a spreadsheet for greater visual clarity. We could open containing folders and properties sheets, too, as well as save selected items as text, HTML, or CSV files. We could even copy items using Explorer. The program includes a basic but effective compiled Help file in its download, but some Windows users might need to open it directly from the program folder. RegDllView's product page also contains useful documentation.
RegDllView displayed all our system's registered objects under the appropriate headings. Selecting any item displayed it in the main window, from which we could display the item's Properties sheet by clicking it. It's nice to be able to open entries directly in RegEdit, too. Of course, we always recommend against making unnecessary changes in the Registry without being absolutely sure of what you're doing. We didn't need to make any changes, but RegDllView made it easy to verify that some system tweaks we'd made to several keys were still in play. This free tool not only does something fairly unique and undeniably useful, but it also makes it extremely easy.