Word cannot register your account. The provider where you are trying to publish is unavailable. Contact your provider for assistance.
Problem:
I tried publishing a blog post to SharePoint blog from Microsoft Word 2013 from “File >> Share >> Publish to Blog”. While registering a new SharePoint blogging account, got this error message, “Word cannot register your account. The provider where you are trying to publish is unavailable. Contact your provider for assistance.” 
Solution:
Go to SharePoint 2013 Central Administration >> Manage Web Applications >>Web Application General Settings >> Set the option for “Allow user name and password from the API” to Yes.
Another cause and solution:
If your current logged-in Windows user account isn’t the same as your SharePoint account, You may get this error! Set your Internet Explorer’s settings to prompt user name and password. Delete your cookies and try again. You should get this “Account registration successful” message.
I am also facing problem with blogger. Plz help.
I am getting this error with blogger.. can u help
Your solution is not clear. And you’re not telling us what is the problem…
It would be nice if you show the picture of those methods
Where is SharePoint 2013 Central Administration ? Pls tell step by step.. from where can I find it? thanks!
Well, SharePoint 2013 Central administration will be hosted in one of your SharePoint Server. You got to Login and find out!