PUM.Optional.Userinit is Malwarebytes detection name for a potentially unwanted modification in the Windows registry that could provide a startup location for malware.
A filename would be added to the following registry value data to gain persistence:
a change would be made to the value:
Files called from this location will be triggered shortly before the logon screen.
Malwarebytes can modify this registry value data back to its Windows default setting without user interaction.
When a Potentially Unwanted Modification (PUM) is detected on your computer, Malwarebytes for Windows does not know whether it was authorized. Optimization software, malware, and Potentially Unwanted Programs (PUPs) are known to make these types of changes, hence they are regarded as potentially unwanted by design.
To have Malwarebytes for Windows ignore a PUM, you must add the PUM to the Allow list. Here’s how to do it.