I have downloaded many freeware and such we will say and after the uninstallation of these softwares there are hundreds if not thousands of remnants of each program in the registry. My question is, other than using normal procedures such as REGCURE, most registry cleaners do not erase these left over keys(including regcure and other utilties), so how do you delete them from the registry???

i have downloaded INTERNET DOWNLOAD MANAGER the free trial version then after i have used it for a couple of times it expired then i have made a COMPLETE uninstallation
but i have noticed that the connection speed decreased significantly so how can i repair (restore) the changed registry configuration back to default ??