[peaglert]

Hello, how do you remove all calibre references from the OPF? I'm new and not sure have to remove all the prefixes or where to find them.

I'm trying to solve these two errors below.

[ERROR]OEBPS/content.opf: 2,213: URL expected instead of calibre:
[ERROR]OEBPS/content.opf: 17,46: Undecleared prefix: calibre



Thank you