I got the advise to disable the virus scanner integration with Outlook. Isn’t that a bad thing to do?
No, not really. In fact, disabling it will probably give you less headaches than leaving it on. You probably were advised to disable it after experiencing some issues with sending or receiving mail, mail getting lost or mail being crippled.
Built-in Outlook security doesn’t allow code to be executed when viewing your mail in the Reading Pane so it is impossible to get infected by a virus by opening the mail itself. In order to get infected you’ll have to actually double click the virus attachment yourself for it to be executed.
As a safety precaution, Outlook doesn’t allow you to double click on certain attachments that could contain a virus (click here for more info on that). In case that you have another attachment that contains a virus, the on-access scanner (the one that runs in the background) of your virus scanner will kick in and prevent it from being executed. Since the on-access scanner uses the same anti-virus definitions as the scanner that integrates with Outlook, having the integration will not provide an extra layer of security and thus you can safely disable this form of integration.
How to disable this integration depends on your virus scanner solution. Some have a control panel of their own where you can disable this component but this often isn’t enough as while it may disable the function, it won’t disable its integration. Sometimes they expose themselves as an addin in Outlook so you can disable it via Outlook. This usually could result in security alerts though by your virus scanner and also from Windows if your virus scanner notifies Windows about security alerts.
The best way to counter this, for most virus scanner solutions, is to uninstall the virus scanner completely (additionally run a cleanup tool if your virus scanner vendor offers one) and then reinstall your virus scanner again but during the setup make sure you specify not to install the mail scanning component. The documentation of your virus scanner solution can tell you more about how to install only certain components if it is not directly clear to you how to do it.