Here in the UK, I was receiving one "Windows Store failed to sync machine licenses. Result code 0x80070490" error every day but have not had any errors since November 19 when two updates were installed:
Security Update for Windows 8.1 for x64-based Systems (KB3011780)
and
Update for Windows 8.1 for x64-based Systems (KB3000850)
The latter was an optional update which I selected to install.
Could it be that one of these has solved the problem?
Not here. I live in Germany and the error is still being logged once a day after those updates.
I'm back to the workaround (executing the task as SYSTEM instead of USER). I have no apps installed and use a local user account so its alright for me.
Kind regards