[Hedjuk]

I'm connecting my Kindle Fire to Calibre utilizing Mac OS X 10.7.4. I could previously download the Economist, have it automatically convert and send to the Kindle, but for some reason, I can't anymore. Sometimes it'll send to the Kindle, but if I open the document, there is no content there. Other times, it says there is failure in connecting to the Kindle, and won't send it at all.

I tried downgrading Calibre from 0.8.54 to 0.8.53, but nothing has helped. I have run Calibre in debug mode and the log is below:
_________________________

[Errno 16] Resource busy

Traceback (most recent call last):
File "site-packages/calibre/gui2/device.py", line 82, in run
File "site-packages/calibre/gui2/device.py", line 412, in _upload_books
File "site-packages/calibre/devices/usbms/driver.py", line 267, in upload_books
File "site-packages/calibre/devices/usbms/cli.py", line 59, in put_file
IOError: [Errno 16] Resource busy

calibre Debug log
calibre 0.8.53
Darwin-11.4.0-x86_64-i386-64bit
Darwin
('Darwin', '11.4.0', 'Darwin Kernel Version 11.4.0: Mon Apr 9 19:32:15 PDT 2012; root:xnu-1699.26.8~1/RELEASE_X86_64')
Python 2.7.1
OSX: ('10.7.4', ('', '', ''), 'x86_64')
Starting up...
Started up in 5.35 seconds with 10 books
Job: 1 Get device information started
DeviceJob: 1 Get device information done, calling callback
DeviceJob: 1 Get device information callback returned
Job: 2 Get list of books on device started
DEBUG: 0.0 USBMS: Fetching list of books from device. Device= KINDLE_FIRE oncard= None
DEBUG: 0.0 USBMS: dirs are: /Volumes/KINDLE/ Documents
DEBUG: 0.0 USBMS: scan from root True /Volumes/KINDLE/
Job: 1 Get device information finished
No details available.
DEBUG: 0.2 USBMS: count found in cache: 19, count of files in metadata: 19, need_sync: False
DEBUG: 0.2 USBMS: Finished fetching list of books from device. oncard= None
DEBUG: 0.2 USBMS: Fetching list of books from device. Device= KINDLE_FIRE oncard= carda
DEBUG: 0.2 USBMS: Fetching list of books from device. Device= KINDLE_FIRE oncard= cardb
DeviceJob: 2 Get list of books on device done, calling callback
DeviceJob: 2 Get list of books on device callback returned
Job: 2 Get list of books on device finished
No details available.
Job: 3 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] started
Device using plugboard azw3 KINDLE_FIRE None
Setting metadata in: The Economist [Sun, 03 Jun 2012] at: /var/folders/d5/pk6jbd3d62vchy5gk47tpp2h0000gn/T/calibre_0.8.53_tmp_a7vB0V/_ZzUoxcaltmpfmt.azw3
DEBUG: 8.5 USBMS: uploading 1 books
DEBUG: 8.8 USBMS: finished uploading 1 books
DeviceJob: 3 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] done, calling callback
DEBUG: 8.9 USBMS: adding metadata for 1 books
DEBUG: 8.9 USBMS: finished adding metadata
DeviceJob: 3 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] callback returnedJob: 3 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] finished
No details available.

Job: 4 Send metadata to device started
DEBUG: 8.9 USBMS: starting sync_booklists
DEBUG: 8.9 USBMS: finished sync_booklists
DeviceJob: 4 Send metadata to device done, calling callback
DeviceJob: 4 Send metadata to device callback returned
Job: 3 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] finished
No details available.
Job: 4 Send metadata to device finished
No details available.
Job: 5 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] started
Device using plugboard pdf KINDLE_FIRE None
Setting metadata in: The Economist [Sun, 03 Jun 2012] at: /var/folders/d5/pk6jbd3d62vchy5gk47tpp2h0000gn/T/calibre_0.8.53_tmp_a7vB0V/Uh5ru1caltmpfmt.pdf
Worker Launch took: 0.178230047226
Job: 6 Write pdf metadata finished
Write pdf metadata
Fontconfig error: Cannot load default config file
<</Info 2 0 R/Root 3 0 R/Size 3102>>

Job: 6 Write pdf metadata finished
Write pdf metadata
Fontconfig error: Cannot load default config file
<</Info 2 0 R/Root 3 0 R/Size 3102>>

DEBUG: 127.7 USBMS: uploading 1 books
WARNING: First attempt to send file to device failed
DeviceJob: 5 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] done, calling callback
DeviceJob: 5 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] callback returned
Job: 5 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] finished
[Errno 16] Resource busy

Traceback (most recent call last):
File "site-packages/calibre/gui2/device.py", line 82, in run
File "site-packages/calibre/gui2/device.py", line 412, in _upload_books
File "site-packages/calibre/devices/usbms/driver.py", line 267, in upload_books
File "site-packages/calibre/devices/usbms/cli.py", line 59, in put_file
IOError: [Errno 16] Resource busy

Job: 7 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] started
Device using plugboard azw3 KINDLE_FIRE None
Setting metadata in: The Economist [Sun, 03 Jun 2012] at: /var/folders/d5/pk6jbd3d62vchy5gk47tpp2h0000gn/T/calibre_0.8.53_tmp_a7vB0V/mEHCuWcaltmpfmt.azw3
DEBUG: 170.6 USBMS: uploading 1 books
Devi[Errno 16] Resource busy: u'/Volumes/KINDLE/Documents/Economist [Sun, 03 Jun 2012], The_2012-6-3.azw3'

Traceback (most recent call last):
File "site-packages/calibre/gui2/device.py", line 82, in run
File "site-packages/calibre/gui2/device.py", line 412, in _upload_books
File "site-packages/calibre/devices/usbms/driver.py", line 267, in upload_books
File "site-packages/calibre/devices/usbms/cli.py", line 50, in put_file
File "site-packages/calibre/utils/filenames.py", line 182, in case_preserving_open_file
IOError: [Errno 16] Resource busy: u'/Volumes/KINDLE/Documents/Economist [Sun, 03 Jun 2012], The_2012-6-3.azw3'

[Errno 16] Resource busy: '/Volumes/KINDLE/Documents'

Traceback (most recent call last):
File "site-packages/calibre/gui2/device.py", line 82, in run
File "site-packages/calibre/gui2/device.py", line 412, in _upload_books
File "site-packages/calibre/devices/usbms/driver.py", line 267, in upload_books
File "site-packages/calibre/devices/usbms/cli.py", line 50, in put_file
File "site-packages/calibre/utils/filenames.py", line 190, in case_preserving_open_file
OSError: [Errno 16] Resource busy: '/Volumes/KINDLE/Documents'

ceJob: 7 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] done, calling callback
DeviceJob: 7 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] callback returned
Job: 8 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] started
Device using plugboard pdf KINDLE_FIRE None
Setting metadata in: The Economist [Sun, 03 Jun 2012] at: /var/folders/d5/pk6jbd3d62vchy5gk47tpp2h0000gn/T/calibre_0.8.53_tmp_a7vB0V/Gk7NAmcaltmpfmt.pdf
Job: 7 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] finished
[Errno 16] Resource busy: u'/Volumes/KINDLE/Documents/Economist [Sun, 03 Jun 2012], The_2012-6-3.azw3'

Traceback (most recent call last):
File "site-packages/calibre/gui2/device.py", line 82, in run
File "site-packages/calibre/gui2/device.py", line 412, in _upload_books
File "site-packages/calibre/devices/usbms/driver.py", line 267, in upload_books
File "site-packages/calibre/devices/usbms/cli.py", line 50, in put_file
File "site-packages/calibre/utils/filenames.py", line 182, in case_preserving_open_file
IOError: [Errno 16] Resource busy: u'/Volumes/KINDLE/Documents/Economist [Sun, 03 Jun 2012], The_2012-6-3.azw3'

Worker Launch took: 0.256733894348
Job: 9 Write pdf metadata finished
Write pdf metadata
Fontconfig error: Cannot load default config file
<</Info 2 0 R/Root 3 0 R/Size 3102>>

Job: 9 Write pdf metadata finished
Write pdf metadata
Fontconfig error: Cannot load default config file
<</Info 2 0 R/Root 3 0 R/Size 3102>>

DEBUG: 179.4 USBMS: uploading 1 books
DeviceJob: 8 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] done, calling callback
DeviceJob: 8 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] callback returned
Job: 8 Upload 1 books to device:The Economist [Sun, 03 Jun 2012] finished
[Errno 16] Resource busy: '/Volumes/KINDLE/Documents'

Traceback (most recent call last):
File "site-packages/calibre/gui2/device.py", line 82, in run
File "site-packages/calibre/gui2/device.py", line 412, in _upload_books
File "site-packages/calibre/devices/usbms/driver.py", line 267, in upload_books
File "site-packages/calibre/devices/usbms/cli.py", line 50, in put_file
File "site-packages/calibre/utils/filenames.py", line 190, in case_preserving_open_file
OSError: [Errno 16] Resource busy: '/Volumes/KINDLE/Documents'