Online backup failures

I'm having frequent online backup failures and warnings, intermixed with a few successful online backups. Online failures are mixed, such as: 1) failed to parse the XML; 2) Failed to peek data from the SSL connection (lots of these failures), and; 3) Trying to set shared lock to the file stream/Shared lock is not supported by the file stream. Out of 36 days, I have 6 successful online backups. My settings are for daily backups (around 1am Eastern time). I am using 80% of my 250GB online storage and the backup is fully replaced each backup. What is the problem? I'm running Win7 64-bit, 16GB RAM -- it's a high end system.