If you want to run Merak and IIS 5.0 on the same (default) HTTP/HTTPS/SMTP ports, you must disable the IIS 5.0 socket pooling. Please consult the following Microsoft Knowledge Base articles for more information:

• IIS Binds To All Available IP Addresses When It Starts
• How to Disable Socket Pooling
• XCON: How to Disable Internet Information Services Socket Pooling on the SMTP Service