Especially when you use the monitoring feature, Soft Organizer Pro may let you reverse more of the changes made when you installed software, but often it won’t get everything. It’s up to you if maybe removing a few more leftovers is worth the hassle of using software to monitor installs, and it’s up to you if it’s worth having it running to catch any auto updates that might happen if/when that software can detect any of the common setup routines used for updating software. If you’re running win10, if/when you essentially replace / reinstall the OS every 6 months or so when there’s a version update, lots of accumulated garbage won’t be carried over to the new version anyway [though some will be].
When you install software, it can make all sorts of changes to that copy of Windows. It might add additional software – Microsoft C/C++ runtimes are common – that you’re not told about. It might make lots of changes to the registry – occasionally you might be able to record hundreds of thousands when the Component registry hive is involved – and not all those changes are readily reversable, e.g. when a media player app takes over the file-type associations for every type of media file. If the Windows Installer [.msi setup files] &/or .NET are used, permanent changes are made to each in that copy of Windows. Copies of all or part of the setup files may be added in several folders scattered across your copy of Windows, while Windows defaults, e.g. what files handle what kinds of media, and settings, e.g. Windows Firewall, may be altered. Changes to things like Windows Auto Play & [right click] context menus may be made. There really are no enforced rules when it to installing and uninstalling software.
While Soft Organizer Pro is a step in the right direction, unfortunately there isn’t a great way to keep track of all the changes made when you install a program, and often no way to automatically reverse all those changes. Sysinternals Process Monitor [Microsoft[.]com] will record everything, but filtering out all the data you don’t want is a challenge to say the least, made more difficult because you have to know which changes are due to the software install, and which ones matter. Using before & after snapshots can work, but also has problems… taking a snapshot of all the files on the Windows partition can take an awful long time, while again it’s up to you to decide which changes to files and the registry matter.
Soft Organizer Pro is a compromise that tries to take out most of the guesswork, doesn’t take forever [like a full file snapshot can], and greatly reduces the risk that’s sometimes involved when you reverse changes made. Part of the price you pay for that is Soft Organizer Pro [like every other software uninstaller] will not allow you to undo every change that was made. Marketing claims that Soft Organizer Pro will remove every trace of an app rely on you not knowing that and are inaccurate. Likewise, claims on its web site that Soft Organizer Pro can remove traces [leftovers] from apps it did not monitor during install are overblown – at best it can search for things like registry entries that include an app’s name, which can be a fraction of those entries that were added, while stored copies of all or part of an app’s setup files often do not include the app’s name.
Alternatives… Universal Extractor can often expand an app’s files out of a setup file – like expanding the files in a Zip file – and sometimes that will work to avoid the setup routine and all the changes it may make. If you’re not running win10, the free open source Regshot can track registry and optionally file changes using snapshots – Regshot2 will work in win10, but only records registry changes. I use the free InstallWatch Pro in a win7 32-bit VM – it won’t work in 64-bit Windows & it won’t work in win10. That VM also has very little software installed, because if an app’s setup routine adds a file that’s already there, it won’t be recorded. Installing an app in a VM – or in win10’s Sandbox [when/if that works] – also lets you eliminate installing software that doesn’t do what you want/need. None of this stuff uninstalls anything, but it gives you complete records if you want to try & DIY.
Notes: AFAIK there are no lists of what you can safely remove when it comes to added files or the registry – going over the records from lots of monitored software installations you’ll develop a good sense of what matters & what doesn’t. VMs are a great way to make sure that what you want to remove can be removed safely. A Windows VM is basically a copy of Windows installed on a VHD file, and you can make a backup copy of that VHD file, so if Windows in a VM breaks, you can simply replace [copy / paste] its VHD file and everything is as it was.