I'm having the same problem here. Have tried deregistering and re registering to no avail.
I have built a website already so don't want to lose what I already have. But not being able to update my website plugins because "they contain no files" is affecting development.
You should check if one license key is registered to the one domain only.
If it is, please deregister and register the license key on this domain once more and try to update the plugins/theme like 3-4 times - it should help you.
Comments
this message could mean that your license key is used on more than one domain.
Please use this tool to manage your license keys:
http://forum.muffingroup.com/betheme/discussion/36219/cannot-register-deregister-your-license-key-use-this-tool#latest
thanks
Thanks