I’m using Windows Live Mail 2012 for years with Windows 10 and it always work without any problem. Suddenly, on a PC I received the above message and I had no possibilities to send any message while the reception is working properly. I first reinstall Windows Live without success, the same problem. Then I moved my Mail directory to another PC which has the same configuration and everything worked without any problem. So I can suppose that there is no corruption in my Mail database.

What can I do to solve that problem?

Thanks in advance,