Q:

Unable to Share URLs to Google+

This issue began last week.  Prior to that, I was not having any problems, and I am not aware of any changes to my site or platform. 
Now, when I want to share a new blog or article to Google+, it fails.  Typically I would use the embedded +1 buttons on a specific post and use the expanded box to create my post.  The box comes up, but instead of a nice title and image, it now uses the URL only for the page, and sometimes adds extra characters to the end of the URL.  If I take the URL from the address bar and try to compose a new update directly on Google+, I get the same issue.  If I enter the URL into the Link field on a status update, it usually comes back "could not load website." 
Here's a sample
You'll find Google+ sharing buttons above and below the article.  Sharing to every other network works as expected. 
My site is a Drupal site that has been operating for 10 months.  I am a Drupal developer, but have never encountered an issue like this. 

A:

It appears that requests from the Googler crawler are being rejected by your server.  I tried testing the microdata with the structured data testing tool and it runs into problems connecting to your site.  Other sites work fine. 
If you have access to your site's Apache access logs, I would check those for problems coming to that URL.  You can narrow your search down by looking for the user agent of the crawler: Google (+https://developers.google.com/+/web/snippet/)
My guess is that something changed in your server's configuration that is the cause.  Start with the logs and see what's there. 