On a message board I found a work around for OLW. It seemed that even if OLW seemed to work for one post, the second one would NOT work again.
This is it:
Open up Open Live Writer Blog Settings & enter your Google/Gmail password (I used my Blogger password which is different)
(File >> Options >> Accounts >> Select 'Blog" >> Edit >> Update Account Information)
You will find the Password Box is empty (though user name with be a GUID)
Fill in the password (Google/Gmail) >> Next >> complete the update.
Now I hope it stays working. We’ll see.