Solution
If you manage an MFP device through MarkVision Professional (MVP), you will notice that the PrimarySMTPGateway field is displayed in a specific format and can only be entered in this format. You can see this by clicking the help option displayed for that particular field. This format is the generic format for an IP address, and the only valid entries and characters are listed in the help window. Thus, the only supported format for the Primary SMTP field in MVP is the MVP's IP address.