You need to print or save an email and/or attachments on a network path ( for example \\192.168.2.100\foldername\). This does work while Automatic Email Manager is open only under your Windows session. Since you use it on a desktop or server where people login/logout from time to time you started AEM as a windows service.
However... When you log off Windows, AEM runs as a Windows service and the print or save the email/attachments on the network path doesn't work anymore.
You have this problem because your printer or network driver is not available in Windows services mode when no user is logged to Windows, it is not a problem from Automatic Email Manager but a security from Windows which doesn't have access to all resources when no user is logged.
Anyway you can change this, open the Windows services and edit the service AEM, now in the login panel, change the default account connection to a specific user who has access to the network driver, and it should work as expected.