DLL Killer

DLL Killer finds redundant DLL files that unnecessarily take up space and lets you remove them from the computer to make room for new files. This is a speedy and approachable application that requires minimal user assistance.
Before proceeding any further, you should know that the program hasn't been updated for a very long time and it doesn't work on newer Windows editions. Plus, it doesn't support the 64-bit system architecture type.

Simple installation and GUI

After a fast setup operation that shouldn't give you any trouble, you're greeted by an outdated interface made from a standard window with a plain and simple layout which shows all options provided by DLL Killer.

Find and delete redundant DLLs

The search for junk DLLs can be initialized with one click, as this process is performed automatically. There are two different kinds of results shown: for registry entries of DLL files that don't use any programs, as well as for registry files for inexistent DLLs.
After examining the list with full file paths, you can make a custom selection to remove the DLLs. Alternatively, it's possible to get rid of all unnecessary registry entries. Apart from the fact that you can create registry backups before executing DLL removal operations to be able to restore them later if Windows stability issues occur, there are no more noteworthy options available.

Evaluation and conclusion

We haven't come across any issues in our tests, thanks to the fact that the software utility didn't freeze, crash or prompt error dialogs. As expected, it carried out scan and removal jobs swiftly while remaining light on system resources consumption.
Too bad that it hasn't been updated for such a long time that it doesn't support later Windows versions or 64-bit Windows. Otherwise, DLL Killer offers a simple solution to finding and deleting junk DLLs to free up disk space.