Plugin doesn't show any content

Hello,

I’m trying to use your plugin on my website but it doesn’t work properly.

– if I try to share the homepage, it shows: “Untitled Document”
– if I try to share an internal page where there are galleries or just any other page (like “Biography”), it shows: “IIS 8.5 Detailed Errors – 404.0 Not Found”
– if I try to share a single picture from a gallery, it shows “IIS 8.5 Detailed Errors – 404.0 Not Found” again

At the moment the website isn’t online, but it should work anyway.

Any suggestion?
Thanks in Advance!

https://ww.wp.xz.cn/plugins/custom-share-buttons-with-floating-sidebar/