Error getting License. License Server Communication Problem:

Hi...I've been using Adobe Digital Editions for several years now, but for the last couple of days I've been unable to download ebooks from my library.  I get the above Error message, which also includes: E_STREAM_ERROR:  Not sure what this means.  Checked my authentication info - and that's still fine, If anyone has had this issue before, could you please let me know what the solution is?  I can't get past this error message, so...really frustrating as I can't do anything else with the program!  Thanks.