When I try mounting an .ISO (any file, including the ones I've just created), I just get a spinning blue circle and very poor system performance. It takes forever and it is not going to mount. The virtual CD drive appears just fine, both in explorer and in device manager, but the ISO is not being mounted.
I've tried restarting in safe mode and the mount process went just fine and almost immediately (I'm running an i5 laptop with 8 gigs of RAM and an enterprise-class 200GB SSD).
I do not have any third party ISO tools (apart from WinRAR which is able to open and unpack the ISO file, just as any other archive), and the system is a recently fresh install. I've also tried checking for windows consistency, and everything's OK. Running most recent updates as well, and I've tried disabling antivirus (NOD32 business v5).