ReSieve Help File 

Using ReSieve with firewalls

ReSieve needs to be given full permissions on your act as a server for your local machines, and have permission to access the rest of the Internet. 

There are currently no known issues with ReSieve and firewalls, provided it's allowed to connect on the port it requires.

Using ReSieve with multiple accounts

ReSieve will automatically cope with multiple email accounts; you don't need to bother.

ReSieve will use the same set of Buckets and the same History for all email accounts.