Help - Recurring 'Error communicating with device'

[scarlettruin]

Hi - help please!

I keep getting the 'Error Communicating with Device' when trying to wirelessly connect CC on my samsung tablet to calibre. This occurs regardless of which library I have up, and I've made sure I've updated everything fully.

This is what it says:

calibre, version 1.41.0
ERROR: Error: Error communicating with device

'NoneType' object has no attribute 'set'

Traceback (most recent call last):
File "site-packages\calibre\gui2\device.py", line 86, in run
File "site-packages\calibre\gui2\device.py", line 490, in _books
File "site-packages\calibre\devices\smart_device_app\driver.p y", line 50, in _synchronizer
File "site-packages\calibre\devices\smart_device_app\driver.p y", line 1288, in books
AttributeError: 'NoneType' object has no attribute 'set'

Sometimes, though, this error message comes up, and yet there is still a connection between calibre companion and calibre. I can send things to CC, but it doesn't show what is already on my device.

Any ideas?

[chaley]

Originally Posted by scarlettruin

Hi - help please!

I keep getting the 'Error Communicating with Device' when trying to wirelessly connect CC on my samsung tablet to calibre. This occurs regardless of which library I have up, and I've made sure I've updated everything fully.

This is what it says:

calibre, version 1.41.0
ERROR: Error: Error communicating with device

'NoneType' object has no attribute 'set'

Traceback (most recent call last):
File "site-packages\calibre\gui2\device.py", line 86, in run
File "site-packages\calibre\gui2\device.py", line 490, in _books
File "site-packages\calibre\devices\smart_device_app\driver.p y", line 50, in _synchronizer
File "site-packages\calibre\devices\smart_device_app\driver.p y", line 1288, in books
AttributeError: 'NoneType' object has no attribute 'set'

Sometimes, though, this error message comes up, and yet there is still a connection between calibre companion and calibre. I can send things to CC, but it doesn't show what is already on my device.

Any ideas?

This error indicates that the metadata for a book is corrupted. Which book is a mystery, as is why. My guess is that it is a book that was put into CC's folder and is being found by "scan for missing books", but this is only a guess at this point.

Please post a calibre debug log or send it to calibre_debug_logs at charles dot haleys dot org. You can get such a log by following these instructions.

Please also send me a CC debug log. The instructions for doing that are in the same post referred to above. Please be sure to mention in the email that you are responding to a post on MobileRead.

[scarlettruin]

Originally Posted by chaley

This error indicates that the metadata for a book is corrupted. Which book is a mystery, as is why. My guess is that it is a book that was put into CC's folder and is being found by "scan for missing books", but this is only a guess at this point.

Please post a calibre debug log or send it to calibre_debug_logs at charles dot haleys dot org. You can get such a log by following these instructions.

Please also send me a CC debug log. The instructions for doing that are in the same post referred to above. Please be sure to mention in the email that you are responding to a post on MobileRead.

Thank you for the response, I'm getting the logs now. Will they be able to tell me which book is corrupted? Is there any way to tell if not?

Thanks

[chaley]

Originally Posted by scarlettruin

Thank you for the response, I'm getting the logs now. Will they be able to tell me which book is corrupted? Is there any way to tell if not?

Thanks

It is hard to say. Assuming that my guess is correct then we will probably be able to get close because IIRC. I will know more once I see the logs.
-----
I have received the logs. There seems to be a book in the database that doesn't have a valid book file. Try running CC's "Books with missing files" (in CC's menu) and see if it finds anything. If it does then note the book (if it has a title) then delete it.

[scarlettruin]

Originally Posted by chaley

It is hard to say. Assuming that my guess is correct then we will probably be able to get close because IIRC. I will know more once I see the logs.
-----
I have received the logs. There seems to be a book in the database that doesn't have a valid book file. Try running CC's "Books with missing files" (in CC's menu) and see if it finds anything. If it does then note the book (if it has a title) then delete it.

I ran the 'missing files' search. It came back with two books - one looked normal but I deleted it anyway. The other came up as 'error - no title in metadata', and when i clicked on it, there was no metadata at all. It was just saved in the calibre folder as 'error'. I deleted it too, but strangely enough when it was deleting them, it came up at 4 files that were being deleted. Is there any way of finding out what the 'error' book is in my calibre library?

Thanks again!

[chaley]

Originally Posted by scarlettruin

I ran the 'missing files' search. It came back with two books - one looked normal but I deleted it anyway. The other came up as 'error - no title in metadata', and when i clicked on it, there was no metadata at all. It was just saved in the calibre folder as 'error'. I deleted it too, but strangely enough when it was deleting them, it came up at 4 files that were being deleted. Is there any way of finding out what the 'error' book is in my calibre library?

Thanks again!

First, can you now connect?

From the logs I expected 3 "error" books. I missed the fourth. My eyes aren't what they used to be.

Unfortunately there is no way to know which books were corrupted. The corruption destroyed all the metadata, including the title. You can connect as a wireless device then look in calibre at which books are not "On Device", but of course that depends on you knowing what should be on the device. While connected, the search "ondevice:false" in the library view will list all books that aren't on the device.

You are probably wondering how this happened. We have seen it around 3 or 4 times in the past. Our theory is that incomplete metadata gets into the database because of a crash or a "scan for new books", then that incomplete metadata is corrupted by a database upgrade when upgrading CC. I found one way that this scenario could happen and fixed it. In any event, it happens extremely rarely. You shouldn't see it again. (knock wood)

[scarlettruin]

Originally Posted by chaley

First, can you now connect?

From the logs I expected 3 "error" books. I missed the fourth. My eyes aren't what they used to be.

Unfortunately there is no way to know which books were corrupted. The corruption destroyed all the metadata, including the title. You can connect as a wireless device then look in calibre at which books are not "On Device", but of course that depends on you knowing what should be on the device. While connected, the search "ondevice:false" in the library view will list all books that aren't on the device.

You are probably wondering how this happened. We have seen it around 3 or 4 times in the past. Our theory is that incomplete metadata gets into the database because of a crash or a "scan for new books", then that incomplete metadata is corrupted by a database upgrade when upgrading CC. I found one way that this scenario could happen and fixed it. In any event, it happens extremely rarely. You shouldn't see it again. (knock wood)

Thank you! It does connect now - Hopefully you're right and it won't happen again, but it's fixed now and that's all that matters!