When you are using Outlook Windows, sometimes you might receive a prompt to either allow or deny with the message that says, “a program is trying to send an email on your behalf.”
If you are frequently getting this error, here’s why it happens (with reason and without) and how to fix it.
A program is trying to send an email on your behalf
The most obvious reason is that a program is indeed trying to send an email via Outlook on your behalf but your antivirus is out of date or inactive. If you were expecting a program to send an email on your behalf, you can simply click ‘Allow.’ The warning appears in case you do not have an active antivirus on your computer or if it is out of date.
The simple fix is to update your antivirus.
You can also check in Outlook if your antivirus is up to date and valid.
- Go to File -> Options
- Go to ‘Trust Center’ -> Trust Center Settings
- And then “Programmatic Access” tab.
- At the bottom, you can see if Outlook shows valid antivirus or not.

If it is showing an invalid antivirus, you need to either install a proper antivirus or update the one you already have.
Change Programmatic Access Outlook Settings from Trust Center
To be able to change the settings about Outlook warnings related to suspicious activity (such as another program trying to send an email on your behalf), you must restart Outlook as an administrator.
- Click “Start” on Windows and type “Outlook.”
- Right-click on the “Outlook” program icon and select “Run as administrator.”

If you want to override the warning about another program trying to send an email on your behalf, you can turn it off from inside the “Programmatic access” options. Although, it is not recommended to turn off the warning, as it might pose a threat by some malware that might be again unwanted access and send an email from your address without you knowing.
Trusted Program
But there are often cases where a trusted automatic software has to send an email on your behalf. If you are not there to “allow” when this warning appears, the automated software won’t be able to send emails. If you are absolutely sure that you have set a trusted program to send emails via Outlook on your behalf and you always want to allow it to send automatically (in case when you are not available), you can choose the “Never warn me about suspicious activity” option, but remember that it is not recommended due to security concerns.
On the other hand, if you want to be extra secure and never want another program to send an email before you manually allow it, you can also select “always warn me about suspicious activity” regardless of the antivirus status. Then you will get this warning and allow/deny prompt even if a valid antivirus is installed and is up to date. Although, if another and trusted program often sends an automatic email through Outlook, a constant warning can be quite annoying. Therefore, select the appropriate option as per your needs and security concerns.
Here’s a screenshot of all three options available to you about Outlook warning related to suspicious activity. Remember to start Outlook as an administrator if you are looking to change these settings.

Conclusion
In general, if you are antivirus is up to date and all the add-ins that you have installed have properly integrated the latest security measures, you are unlikely to face this otherwise annoying issue when unexpected. With latest Outlook versions and updated add-ins, it is even less of an issue. It is often a frequent problem with older versions of Outlook.
Hope the article helps in fixing the error/warning that “A program is trying to send an email on your behalf.”