Attach file email is encoded

Hi,

I try to find the solution, but after many research and many try, I did not succeed.

When I try to send a form with file attachment, I received the file encoded in the email.

Exemple :

–b1_65e518c7dc2b689b17dd9897f5e59483
Content-Type: image/png; name=”checklist.png”
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename=checklist.png

iVBORw0KGgoAAAANSUhEUgAAABYAAAAWCAYAAADEtGw7AAAA2klEQVR42tWUUQ3DIBCGJwEJk4CE
SaiESkACDiahAvZQCU1mAAlIQMLGJWx/ctcLBfpSki9pOO7juNLerjFe73tmzYQzpVMmZT4EDz5a
KXm+CEEJWOzWxFLg8xtJzclSj+Nj0h1tgSKdSSnFBwcJmDD9+q2L0XOrSO1epZmgi2U1nq01mcik
jqT0XBOvLBFHlLEF+XXxtNM/818Hgsyv9/gp7qVsgW0TY36DRLmrXWL9w4kU7hXLGJjHxIh7Xu24
GGtc2cAOivXRJWYVtf83tLc/SFR3HSDx034By39kUXS3cYgAAAAASUVORK5CYII=

–b1_65e518c7dc2b689b17dd9897f5e59483–

I tried those solutions (I found them with the magic of Google) :
– Removed all others plugins and changed for the default template; but nothing.
– Deleted the plugins «contact form 7» and re-installed it, but nothing.
– And I checked the writing acces to the upload file and all seems fine.

The only thing that worked was to install another plugin, and the plugin sends the file attachment perfectly. But I love «contact form 7» and want to work with this plugin.

I hope someone will be able to help me.

(Sorry for my english, I speak french).

https://ww.wp.xz.cn/plugins/contact-form-7/