Strange error

This is the second time this machine has gotten this error.
Error 0x0000045A has occurred while loading C:\Program Files\Alwil Software\Management Tools\Install.dll library.

Last time the only fix was to reboot the server. Couldn’t log into the admin console or do anything. Any thoughts?

Very strange indeed…
When does the message appear, exactly? In the avast logs?

What OS is this?

Thanks
Vlk