A Windows registry checker will scan through all the files and folders of a Windows operating system’s registry and mark all the files that are incomplete, inaccurate as well as all those now missing but should be present. Doing this is usually a prelude to the second phasee a registry cleaner will perform. That phase is the part of the operation where the software program reinstates the missing files, restores the incomplete ones to their complete state and repairs the inaccurate entries. In other words, a Windows registry checker is the first step performed as part of a registry cleaner’s one-two punch.