I cannot open the program (desktop version) - it does not respond to the shortcut. The program files show that the program was modified yesterday evening when I was out, and I think the computer was switched off. When I try to reinstall from the website, it says that this cannot be done because the program is already open. I have run malwarebytes and have quarantined the five PUPs it showed. Any suggestions?
Have you tried re-installing it again? You could try disabling anti virus etc to see if something is blocking the running of Manager. Also have a look in Event Viewer Logs.