Weasyprint: w10 error - inflateReset2(libpng16-16.dll)

[ZabeJM]

After install weasyprint on my computer (followin the instructions http://weasyprint.readthedocs.io/en/stable/install.html) i try to execute the test

python -m weasyprint http://weasyprint.org weasyprint.pdf

and i received the next error:
cannot find entrypoint in procedure inflateReset2 in dll file C:\Program Files\GTK-Runtime Win64\bin\libpng16-16.dll

This .dll is in this path.
My machine is a 64-bits architecture, and i have installed all 64bits versions

Where is the problem?

Thanks a lot.
Kind regards

[liZe]

Strange… Did you use GTK's .exe installer, or did you try to clone the repository?

[ZabeJM]

I used a GTK's .exe installer

LiZe, thanks for your support

[liZe]

According to some sources, you may have another (older) version of zlib installed somewhere else in a folder listed in your PATH.

There's unfortunately nothing I can do more than looking for similar issues on the internet, as I don't easily have access to a Windows installation :cry:.

[ZabeJM]

I'm looking my environment variables and i don't find any reference to zlib.

Yesterday I forget to send my traceback log.
When i close the libpng16-16.dll error (on a message box) the traceback writes this:

python -m weasyprint http://weasyprint.org weasyprint.pdf Traceback (most recent call last): File "C:\Python27\lib\runpy.py", line 163, in _run_module_as_main mod_name, _Error) File "C:\Python27\lib\runpy.py", line 111, in _get_module_details __import__(mod_name) # Do not catch exceptions initializing package File "C:\Python27\lib\site-packages\weasyprint\__init__.py", line 375, in <module> from .css import preprocess_stylesheet # noqa File "C:\Python27\lib\site-packages\weasyprint\css\__init__.py", line 29, in <module> from . import computed_values File "C:\Python27\lib\site-packages\weasyprint\css\computed_values.py", line 16, in <module> from .. import text File "C:\Python27\lib\site-packages\weasyprint\text.py", line 18, in <module> import cairocffi as cairo File "C:\Python27\lib\site-packages\cairocffi\__init__.py", line 41, in <module> cairo = dlopen(ffi, 'cairo', 'cairo-2') File "C:\Python27\lib\site-packages\cairocffi\__init__.py", line 38, in dlopen raise OSError("dlopen() failed to load a library: %s" % ' / '.join(names)) OSError: dlopen() failed to load a library: cairo / cairo-2

Thx

[liZe]

OK, the real original error is probably OSError: dlopen() failed to load a library: cairo / cairo-2, meaning that cairo in not available in PATH.

I don't know how you can get C:\Python27 if you carefully followed the install instructions asking to install Python 3.6 :wink:. Quoting the install page:

Dear Windows user, please follow these steps carefully. Really carefully. Don’t cheat.

There's nothing more I can say.

[liZe]

@ZabeJM Did you try anything new?

[Rarefy-Dev]

Hello,
Your mileage may vary but I was fighting with this particular issue all day yesterday. Was pulling my hair out. Ran across this article (https://github.com/syncthing/syncthing-gtk/issues/273) and with a nothing left to lose kind of vibe finally fixed it by moving the GTK/bin files out of the default directory (that had spaces in it) to a directory with no spaces and that fixed my issue. Good Luck.

[liZe]

@ZabeJM I'm closing this issue, I hope that you've found a solution or that @Rarefy-Dev's comment will help you.

[kummerer94]

Just letting you know that this error is still occurring and that @Rarefy-Dev's comment did not fix it for me. Still trying to find a solution.

[kummerer94]

Okay, I fixed it already.

There were two copies of zlib1.dll in my path (check with `where zlib1.dll´). I had to remove the other one and it worked.

I found this solution here: https://github.com/Alexpux/MINGW-packages/issues/813

[theHopeCollective]

So which copy of zlib1.dll did you remove?

[kummerer94]

I removed the one that was not located in the GTK3-Runtime Win64\bin\ directory. I thought the version of zlib included here might work best with the other dlls of GTK3. As it turns out, it does. I currently have no problems running weasyprint.

[hotenov]

Thanks @kummerer94 !
It helped me too. (_for google users I'll describe my steps_)
In my case, the output of command: _where zlib1.dll_
was:
C:\PostgreSQL\pg10\bin\zlib1.dll
C:\Program FilesGTK3-Runtime Win64\bin\zlib1.dll

Only I didn't removed the PostgreSQL folder from PATH, I moved the GTK3 folder at the beginning of my PATH list using Move Up button

Remember! You need restart your PC to apply the changes. _(Without it, the magic of the Windows doesn't work :)_

After that the command:

python -m weasyprint http://weasyprint.org weasyprint.pdf

saved PDF file for me. I was happy!