From nookDevs

Calibre

Calibre is a wonderful book organization/conversion program which is very useful to people with ebook readers and large sideloaded libraries. http://calibre-ebook.com/

2.4.1 Softroot/ROM

2.4.1 Changed the vendor ID of the nook, this causes Calibre to stop seeing the nook and its inserted media card. This can be fixed with relatively little effort thanks to some sleuthing by jfeise.

These Instructions Should Work on Any Platform

NEWS: This vendor ID has been added to Windows versions of Calibre - 0.7.11 and later

NEWS: This vendor ID has been added to Linux versions of Calibre - 0.7.12 and later

Steps

1. Find calibre/devices/nook/driver.py,

on ubuntu this is at:

 /usr/lib/calibre/calibre/devices/nook/driver.py

In windows this is at:

  \Calibre2\Lib\site-packages\calibre\devices\nook

You shouldn't need to much though if you keep your Calibre updated as it has supported the revised Vendor ID from version 0.7.11

2. Once you have this file, set the VENDOR_ID to the following

     VENDOR_ID   = [0x18d1]

3. Restart Calibre, un-plug and re-plugin your nook.

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