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You may experience difficulties sending emails after the installation of AVG and the Personal Email Scanner plug-in. In addition, there may be other reasons why emails were returned erroneously to the sender that are unrelated to AVG (for example: failed authentication of the SMTP server, internet connection difficulties, termination of a dial-up internet connection by Outlook Express, etc.).
Disabling the outgoing email scanner may solve these problems or, at the very least, help determine if AVG is causing the difficulty.
Launch the AVG Control Center (by double-clicking on the AVG icon in the system tray)
Double-click on the Email Scanner component
Choose Personal Email Scanner from the list of installed plug-ins
Click on the Properties button
Click on the Servers tab, select the SMTP email server and click on Modify button
Disable the Activate this server and use for sending/receiving e-mail option in the new window dialog
Apply the new settings by clicking the OK button.
Note that the security of your computer is not compromised by disabling scanning of outgoing email. The incoming email scanner is still active and protecting your computer.
http://www.grisoft.com/doc/42/lng/us/tpl/tpl01
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