Note could not be synced the content is not valid

[evernote-nerd 0]

my note sync were working fine. Not sure if I added some new notes but I start getting this error while trying to sync the note.

2017-10-11 23:19:01  [ENSyncEngine] INFO: Syncing note: XXX
2017-10-11 23:19:01  [ENSyncEngine] ERROR:   exception updating note XXX on server
2017-10-11 23:19:01  [ENSyncEngine] ERROR: EDAMUserException(errorCode:11,parameter:"Illegal to contain CDATA")
2017-10-11 23:19:02  [ENSyncEngine] INFO: Sending linked notebook changes...

[gazumped 11,652]

Hi.  Seems like there's an issue with at least one note.  If you can identify it from a recent created or updated date,  you could move one or more notes to a Local (unsynced) Notebook and retry - move notes back into your synced system when you've identified the problem.  Create a new note and copy/ paste the problem note(s) content again to create a new copy note and try to sync that...