I'm not certain if you are using the term deleted instead of uninstalled (a fairly common mix and match of terms),
but for future reference, if you have deleted or tried to delete the Malwarebytes folder rather than uninstalling...
If you deleted (some of) the Malwarebytes install folder from Program Files there will be Registry keys and other folders and files
in places such as the AppData folders that will not have been removed as well. The Registry keys in particular can cause problems.
The Registry keys can prevent removing the title from Apps & Features or Programs and Features, and can also prevent reinstalling
the software because Windows will think it's still installed.
With the exception of Security programs such as Malwarebytes, where the uninstaller provided by the software developer
is a safer option, always uninstall programs via Settings > Apps > Apps and Features, or Programs and Features (in Control Panel).
Rebooting after uninstalling is also important with some programs (security and drivers in particular).
Many programs leave folders and file after uninstalling via Windows, and they can generally be deleted, but due to the nature of Security
programs there are some folders and files that cannot be deleted, which is why it is recommended to use the uninstaller provided
by the developer of the Security program.
- If you did uninstall Malwrebytes via Windows and still have folders left over you may find that if you reinstall Malwarebytes
and uninstall it again using their uninstaller you will be more successful getting rid of all Malwarebytes folders and files.
If you are unable to reinstall Malwarebytes, there shouldn't be much more than a few megabytes of drive space wasted by
those folders and files, and they should not conflict with anything else.
- I'm not sure it would help in this instance, but if your have a System Restore point from before the time you deleted\uninstalled
Malwarebytes, rolling back to that time may help restore Malwarebytes.
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