We use Nextcloud for this.

Hello.

I run multiple email servers for different companies on multiple servers in different locations all onprem. Some are CTX containers on Proxmox some are just older physical servers.

Do not even try to run it on VPS or on any low reputation IP’s or internet domains.

Use a different internet domain (not subdomain) and IP for your marketing/newsletter/e.t.c. or such that are susceptible for blacklisting, so your business email still get trough.

Please correct me if I’m wrong… but you are an IT Manager at a company that have outsourced its own email server and have no idea on how your internal email system is working and also nobody from the IT department has no idea on how it works, so your last resort is to ask on Reddit ?

rtorrent as torrent client + rutorrent as webUI