Lost Formats in Calibre Library

[mitch13]

I have searched for something similar but had no luck. The closest I got was one where a Calibre user had modified/deleted Calibre files via the OS instead of using the Calibre GUI. I always use mods via the Calibre GUI.
I am using Windows 7 and decided to transfer my Calibre library to a USB (64Gb)
and run the Calibre Portable version so that I could use this USB on multiple PCs/Laptops.
Prior to this I was running the 64-bit version on my PC. I copied (via the OS) the complete Calibre library and then run the Calibre Portable loaded on the USB.
Whether I had the problem before this, I do not know but now find a large number of books totally without any formats. I have a very large library and the books missing formats is around 14% of my library.
Does anyone have any thoughts on how this might have happened or a cure!

Thanks

mitch13

[aleyx]

This could look like a corrupted filesystem, due to having removed the USB key without first having the OS eject it.

USB writes are async. The OS may tell you that the copy process to the USB key is done and OK, but it lies. That's why the key still blinks for a while afterwards, and that's why you should never, never remove the key before ejecting it by whatever means the OS offer you.

If you always ejected the key properly... then I have no idea right now.

[BetterRed]

Originally Posted by mitch13

Whether I had the problem before this, I do not know but now find a large number of books totally without any formats. I have a very large library...

If the library is still on your hard disk (your post says you copied it), then open it in calibre and see if it has any books without any format files - search formats:false

If you have a "very large library" then hopefully you have a backup - have a look at it to see if there are missing formats.

BR

[mitch13]

Thanks aleyx and BetterRed.

No, I always remove USB via the OS dismount option.

Will look at original library.

Thanks