Spybot – Search & Destroy will uninstall from the Windows Add/Remove Software control panel without problems. The following directories will not be removed during the uninstall procedure, if you want those folder to be deleted, you will have to remove them by hand:
Windows XP: C:\Documents and Settings\All Users\Application Data\Spybot – Search & Destroy\
Windows Vista or Windows 7 or Windows 8: C:\ProgramData\Spybot – Search & Destroy (Please note that the Application Data Folder is hidden. So if you cannot find this folder please check your folder properties.)
Explanation: this folder contains the backup (the quarantined files) that Spybot 2 creates. If the Uninstall would remove this folder as well, this would mean that those backups would be gone. We saw it a few times that new users uninstalled Spybot 2 in panic after they have experienced a small problem, thus removing the backup that would have undone any changes.