[BetterRed]

@Calibre69 - One of the features of Onedrive (Microsoft's equivalent of Dropbox, Google Drive etc) is that it can maintain a replica of designated folders on MS's cloud servers. A recent version of Windows added the user's Documents, Pictures, and Music folders to the default list of folders Onedrive will replicate to the cloud.

Prior to calibre version 3.30 a new install of Calibre would create its default library ("Calibre Library") in the users Documents folder. The design of the calibre software assumes it has exclusive access to the current library. But the advent of Onedrive's replication of the Documents by default means calibre and Onedrive are trying to access the same data concurrently.

Since calibre version 3.30, the Welcome wizard creates the default library in the users Home directory, which removes it from Onedrive's default list of folders to replicate to the cloud.

If you want to keep a copy of your library on your Onedrive 'account' use a file synch tool that can interoperate with Onedrive - most of them can.

I won't speculate why things work on your ASUS and not on your HP, there are too many variables at play. I suggest you move your calibre libraries out of the Documents folder on both computers.

BR