So sorry for the delay, BR. Lesson learnt! Would never use those things again
SFC didn't help, so I'm backing up my data in case 'Repair' screws up anything.
If I'm forced to do a fresh OS install, should I copy those 2 folders (C:\Users\Selva\Documents\Calibre Library and C:\Users\Selva\AppData\Roaming\calibre) from my backup, before beginning to install Calibre?
If not, could you guys please advise what would be the right way to get Calibre up and running with my existing book collection?
Thanks so very much for your time and comments..