Images not uploading (issues with zlib compression)

Hi,
I a getting an error while uploading images to the server (at the time of creating new articles).It breaks before creating a preview.
I can see this error in debug.log:

“failed to delete buffer zlib output compression”

I have tried to debug & it seems to break after calling move_uploaded_file function in upload-handler.php
Any pointers would be highly appreciated.

I must add, everything was working fine on my local wamp server.
Thanks.

https://wordpress.org/plugins/social-articles/