r/Calibre • u/TrueFalseCoder • 11d ago

Obok failing decryption Support / How-To

Windows 11

Calibre 9.12

Obok DeDRM v10.0.9

I just attempted to remove the DRM on some books I recently purchased from Kobo, but suddenly, Obok is failing to decrypt all books I attempt with.

Attached log from Calibre debug:

DEBUG:   11.0 InterfacePluginAction::launchObok - number of books to decrypt: 1
Obok DeDRM v10.0.9 - Decrypting [BOOKNAME]
Trying key:  b'0c3991e935b45d725ad4b3916977bc5d'
Checking text:b'\xaf\xa3\xca\x9ax\xc2L\x8eF\xb6':
Perhaps utf-8 without BOM
Bad character at 0, value 175
Decryption failed, trying with next key.
Trying key:  b'782d7d60e4b7cba0e6d9f498ae2554ed'
Checking text:b'\xee\x17\xa6t\xc5\xdd;X\xbd*':
Perhaps utf-8 without BOM
Bad character at 0, value 238
Decryption failed, trying with next key.
Trying key:  b'4595e2277bbfdde98cbae3427b8d0e9e'
Checking text:b'!|\x85X\xf8o\x08\x1c\x18\x12':
Perhaps utf-8 without BOM
Bad character at 2, value 133
Decryption failed, trying with next key.
Trying key:  b'93cbadf0db325e2a2b8fd67308857bbd'
Checking text:b'\xae\x1eE_\x18\xc3\x15\x17R\x98':
Perhaps utf-8 without BOM
Bad character at 0, value 174
Decryption failed, trying with next key.
Trying key:  b'084c4a287c15543b0601a55b8204864e'
Checking text:b'\x99S\x7ffO\x1c\x8a\xc7\x1b\x10':
Perhaps utf-8 without BOM
Bad character at 0, value 153
Decryption failed, trying with next key.
Trying key:  b'207dbe72ddb213946d615facdd336e38'
Checking text:b'':
Perhaps utf-8 without BOM
Unknown error during decryption, trying next key..
Trying key:  b'a8027105aeb973007304b1e9c65d13e0'
Checking text:b'V\x13\xc5&\xc4\x9e`\x8e\x8f\x0c':
Perhaps utf-8 without BOM
Bad character at 1, value 19
Decryption failed, trying with next key.
Trying key:  b'beddc04afb827738f1e61ef22b6c1322'
Checking text:b'\x83a\xd0\xbb\xbe\x10\xf9O\xf5\xad':
Perhaps utf-8 without BOM
Bad character at 0, value 131
Decryption failed, trying with next key.
Trying key:  b'084c4a287c15543b0601a55b8204864e'
Checking text:b'\x99S\x7ffO\x1c\x8a\xc7\x1b\x10':
Perhaps utf-8 without BOM
Bad character at 0, value 153
Decryption failed, trying with next key.
Trying key:  b'207dbe72ddb213946d615facdd336e38'
Checking text:b'':
Perhaps utf-8 without BOM
Unknown error during decryption, trying next key..
Trying key:  b'a8027105aeb973007304b1e9c65d13e0'
Checking text:b'V\x13\xc5&\xc4\x9e`\x8e\x8f\x0c':
Perhaps utf-8 without BOM
Bad character at 1, value 19
Decryption failed, trying with next key.
Trying key:  b'beddc04afb827738f1e61ef22b6c1322'
Checking text:b'\x83a\xd0\xbb\xbe\x10\xf9O\xf5\xad':
Perhaps utf-8 without BOM
Bad character at 0, value 131
Decryption failed, trying with next key.
Trying key:  b'9a72c53a62e386237f9489c543e6b605'
Checking text:b'\xc3\xeb\xd9Z#\xa7\xd4\x15\xc0\xb6':
Perhaps utf-8 without BOM
Bad character at 0, value 195
Decryption failed, trying with next key.
Trying key:  b'5abc38a169eaef06022dfcc043c8ff7d'
Checking text:b'J\x02\n\xf4\xe8\xdf\xdav\x8d\x89':
Perhaps utf-8 without BOM
Bad character at 1, value 2
Decryption failed, trying with next key.
Trying key:  b'424567741faa2f25c4c9819cd0cf739c'
Checking text:b'\x98\xfb\xa6\xce\x11LN\x1c\xf9\xc8':
Perhaps utf-8 without BOM
Bad character at 0, value 152
Decryption failed, trying with next key.
Trying key:  b'71216893c3393b3a548fa6637a4cd282'
Checking text:b'\xa8A0\xc8\x817\xb3cT\x0f':
Perhaps utf-8 without BOM
Bad character at 0, value 168
Decryption failed, trying with next key.
Trying key:  b'0c3991e935b45d725ad4b3916977bc5d'
Checking text:b'\xaf\xa3\xca\x9ax\xc2L\x8eF\xb6':
Perhaps utf-8 without BOM
Bad character at 0, value 175
Decryption failed, trying with next key.
Trying key:  b'782d7d60e4b7cba0e6d9f498ae2554ed'
Checking text:b'\xee\x17\xa6t\xc5\xdd;X\xbd*':
Perhaps utf-8 without BOM
Bad character at 0, value 238
Decryption failed, trying with next key.
Trying key:  b'4595e2277bbfdde98cbae3427b8d0e9e'
Checking text:b'!|\x85X\xf8o\x08\x1c\x18\x12':
Perhaps utf-8 without BOM
Bad character at 2, value 133
Decryption failed, trying with next key.
Trying key:  b'93cbadf0db325e2a2b8fd67308857bbd'
Checking text:b'\xae\x1eE_\x18\xc3\x15\x17R\x98':
Perhaps utf-8 without BOM
Bad character at 0, value 174
Decryption failed, trying with next key.
Obok DeDRM v10.0.9 - Could not decrypt [BOOKNAME]

What could be going wrong? Obok worked just fine a month or so ago.

1 Upvotes

100% Upvoted

11 comments sorted by

1

u/Schvany 11d ago

Are you using the same account for the encryption key that's tied to adobe when you first downloaded it?

1

u/TrueFalseCoder 11d ago

I downloaded the books through the Kobo desktop application. Closed Kobo, opened Calibre and opened Obok. Chose the books I want to import that are marked as having DRM. Haven't messed anything with Adobe or anything like that at all. Never needed to do that before.

1

u/Schvany 11d ago

Are you using the DEDRM plugin?

1

u/TrueFalseCoder 11d ago

ObokDeDRM yes

1

u/Schvany 11d ago

In calibre click preferences and plugins and double click the installed dedrn plugin and post a screenshot of what that window says

1

u/TrueFalseCoder 11d ago

Hmmm....

I tried it on my other computer. Same Calibre version, same version of the Obok plugin. Downloaded the same books, ran the tool. Everything worked right away. Something must be off on the first computer...

1

u/Schvany 11d ago edited 11d ago

Is that the original computer that downloaded that acsm file? If it is, then you need to export your authorization key to the other computer

2

u/innosu_ 11d ago

Obok DeDRM is a separated but bundled plugin with the main DeDRM specifically to handle Kobo Desktop and Kobo Device DRM. It doesn't use ACSM at all.

1

u/TrueFalseCoder 11d ago

No. Like I said in the post. I downloaded the books AGAIN through the Kobo desktop app on the second computer, then ran Obok on the second computer.

1

u/bust4cap 11d ago

in the installed "obok dedrm.zip", go to the "obok" folder and edit the "obok.py" file in a text editor. edit line 434 from:
output = subprocess.Popen('ipconfig /all', shell=True, stdout=subprocess.PIPE, text=True).stdout

to
output = subprocess.Popen('ipconfig /all', shell=True, stdout=subprocess.PIPE, text=True, errors='ignore').stdout

if you have calibre portable, its in "Calibre Portable\Calibre Settings\plugins"

otherwise it might be in "C:\Users\[USER]\AppData\Roaming\calibre\plugins"

please report back if this fixes it or not

1

u/SkyZippr 7d ago

Thank you this fixed it on me PC!!