Solved Onedrive for business came out of nowhere

After booting this morning, I had an error window saying "We can't sycn your personal files anymore..". I eventually found that this message came from Onedrive For Business which somehow got installed first thing yesterday morning. I didn't install it, and it is suppose to be part of Office 365, which I also don't have (I have Office 2013). When I right click on it in the applications screen, there is an uninstall option which just takes me to the Uninstall or change a program screen, but Onedrive For Business is not listed, only Microsoft OneDrive (which I use) is there.

So how do I get rid of Onedrive for Business?

Update - I restored my system to several days before it showed up, and it install again right after the recovery. I'm also getting the error message upon rebooting.

Update 2 - I turned off One Drive sync, but still got the error window when rebooting.
I disabled One Drive from Startup, and the problem went away, even with One Drive sync turned back on.

Curiously, even with One Drive disabled in Startup, it still appears in the systray, and when the mouse pointer is hovered above its icon, it shows that it s updating. I'm confused, but at least the error window seems to be fixed.

Quit looking everyone! With a little help from the Microsoft forum, I fixed it.
I still have no idea how OneDrive for Business got installed on my desktop, but when I checked Programs and Features in the control panel of my tablet, I saw that "Microsoft OneDrive" was not there. I deleted it from my desktop, and all is well again. Seems that the "Microsoft OneDrive" is really "OneDrive for Business", not the regular OneDrive (which is still functioning). Clear as mud, right?

Before deleting "Microsoft OneDrive":


After uninstalling "Microsoft OneDrive":