Unfortunately I will not offer very good technical advise on this, but read on. > > The fun part is that horde_webmail needs to have php5.6 for almost all of > its packages. > I just looked here to make sure I get the picture: https://www.horde.org/apps/webmail/docs/INSTALL Under prerequisites it says "PHP 5.3.0 or above" and frankly I cannot see how a newer version of PHP would be the source of any serious problems. I could certainly be wrong, but I am suggesting to dismiss that as a potential problem. > Is there any way to install BOTH php 5.6 and php7.0 without them > conflicting? > I'd say throu all the installation in a VM that has an older OS installed, say an OS that says has PHP 5.8 packaged in it. Make sure it works out of that VM before you trying doing things that can lead to more problems that you cannot quickly solve. Given that this is probably in support of your business, I'll give you this piece of "business development" advise: get your mail service working by having a company like Google handle it for free via Gmail first. You can sort out your own mailserver and web-mail items later. In fact, you can have your own mail-server and allow gmail to be the front-end service (via IMAP), which is what users see when they are using email. Horde can be something that you can trouble-shoot later. The idea is that you will, very quickly, get going so that you can focus on the business side first and leave technical details for the time that details can be sorted out. An added benefit is that you do not have to worry about maintaining the reputation of a mail-server if you allow Gmail to handle it all. You will find that you will have to work a bit harder to keep your server off blacklists. I do know that we all prefer to keep the "evil empire" off our e-mailboxes...