system
17
She has Sygate installed, but that’s not the problem. The Windows firewall is disabled.
She never used a version of Avast other than 4.5.549, the settings of her e-mail-account are correct. I checked everything several times.
Like I said before, the problem is solved when she unchecks the ‘scan outgoing e-mail’-box in the Avast SMTP-settings. So, I guess this is an Avast-problem.