In most cases, ORF is not the only software scanning emails on your server: other components (like the email filtering module of your resident anti-virus scanner, Content Filtering feature of Exchange, etc) may reject, alter or divert the email before ORF could test it.

By default, ORF has lower priority than other components. If you want ORF to filter emails first, the priorities have to be changed.

Changing Priorities on Exchange 2003/2000 or IIS SMTP servers

The filtering order depends on the SMTP Event Sink priorities. To check the SMTP Event Sinks currently installed:

1. Download the file smtpreg.zip.
2. Extract the ZIP archive contents to any folder on your server where ORF runs.
3. Start a command prompt and enter to the directory where you extracted the archive contents to.

4. Run the script as:

   cscript smtpreg.vbs /enum > sinks.txt
   

   A new file called sinks.txt will be created in the current folder, which contains the event sink binding list of IIS SMTP and their priorities (lower number indicates higher priority). ORF binds with the following names: VS_ORFEnterprise_RCPT, VS_ORFEnterprise_EOD (for incoming emails, one for the Before Arrival filtering point, one for the On Arrival Filtering Point) and VS_ORFEnterprise_OUTBOUND (the latter is triggered when an email is sent out, this is required for the Auto Sender Whitelist feature).

5. To change the priority priority of the ORF SMTP Event Sinks to 1000 on the first SMTP virtual server instance, run the following commands:

   cscript smtpreg.vbs /setprop 1 OnInboundCommand "VS_ORFEnterprise_RCPT" Source Priority 1000
   cscript smtpreg.vbs /setprop 1 OnInboundCommand "VS_ORFEnterprise_EOD" Source Priority 1000
   

Please note that the priorities are restored to their default state after you upgrade or re-install ORF. Other software may also change the priorities without prior notice (e.g., Exchange updates).