Error 500 when sending post by WLW

Hi,

I still have an error 500 when I send post by using WLW.
this error pop up at the end of the process to send a post to the blog.

The post is well sent but because of this error, my post stay in the list of draft post in place of going to the list of Post Sent.
The problem I have to delete the post from the draft list in WLW and by the way the post is remove from my computer, so I have no backup in case of server problem

I don't know if it's related but the post is not autopost to any social network as well.

Another issue is the category selected in WLW is not kept by EB5, in place I have the one selected as favorite category.

This happening sine the update to EB5, and the last update haven't change anything


Any help to fix all this will be nice.
Thanks in advance