I've been having this strange problem since this morning after starting office laptop from Hibernate. Restart is also not fixing it.
For any program, file, it just says that Windows cannot find the file ...etc . Simple search shows that it comes from anti virus. So, it is coming from Mcafee Host IPS. As soon as I turn that off from Mcaffee tray menu > Quick settings > Host IPS off, programs start working.
And here's a quick fix for this (Right click McAfee icon, then Quick settings, uncheck 'Host IPS - off'):