Three years ago, after building my new system, I noticed the CPU usage was typically approaching 50% while the system was idle. This was a concern because it generates unnecessary heat which in turn affects the CPU’s life span.
It was easy to identify the culprits: Microsoft Outlook 2013 and TrueImage Sync.
I didn’t need Sync, so I disabled that process. Outlook, though, seemed more problematic. I found the answer by Googling.
The problem wasn’t Outlook per se, but its add-ons.
The problem with add-ons has two dimensions. One is they are often installed without your knowledge; the other is they may not be efficient.
You can locate the add-ons by selecting File->Options->Add-Ins. At the bottom of the window is a drop-down menu labelled “Manage:”.
I deselected them all, as I don’t need them, but if I need one later, I can re-enable it.
My PC is now having a well-earned rest.