My client has a subscriber list which includes both potential clients and current clients. They want to send a campaign to target only the potential customers but don't have the time to remove all the current clients from the list. To get around this I suggested importing all the clients into the suppression list so that they don't receive the emails.
The first question is: is that the best way to approach this?
Secondly, some of their clients buy a domain-wide license, so they need to suppress any email address for a list of domains ( *@domain.com ) - is this possible?
The first problem could be solved by using a custom field and then splitting your list into 2 segments. You can read about segments here, http://help.campaignmonitor.com/topic.aspx?t=90
In regards to the domain wide suppression list, unfortunately this is not possible at this time. I have gone ahead and added this to our feature request list though!