PNG image sink error

Hello all!

When trying to display an image on the GUI in GRC, i get the following error:

...

 File "C:\Program Files\GNURadio-3.7\gr-python27\Lib\site-packages\PIL\Image.py", line 385, in _getdecoder

    raise IOError("decoder %s not available" % decoder_name)

IOError: decoder zip not available

When looking up the IOError it seems like it's a problem with ZLIB, or missing zlib files. I am not sure if this is the case though, or how i should fix it.

What am i doing wrong?

I am running GRC 3.7.13.5 on WIN10

//Steffen