We've seen an increase of the inability to login to Battle.net/Hearthstone due to BLZBNTBGS80000011 errors. We would like to gather logs to help our teams resolve these errors.
If you are continuing to get BLZBNTBGS80000011 errors:
- 1. Gather and send us a copy of your Battle.net Logs.
2. Send an email with the zip archive to: firstname.lastname@example.org
3. Use this line for the subject: [XXForumNameXX] [BLZBNTBGS80000011 Errors] 
4. Please include any additional numbers in parentheses in the email body field.
This may not result in an immediate fix for your individual issue, but it will go directly towards getting this sort of issue fixed in general.
Thanks in advance.