Q: using a mac remotely

Mac OS X (10.5.8)

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I'm going to give several options.  I suggest you test and get working at least 2, because it is difficult to run back home and to address an issue if the remote access method you are using stops working.  Having 2 methods gives you options.

Back-to-My-Mac

<Set up and use Back to My Mac - Apple Support>

<http://www.macworld.co.uk/how-to/mac-software/how-set-back-my-mac-mac-os-x-maver icks-3495116/>

<http://www.macworld.com/article/2839080/away-from-home-heres-how-to-access-your- mac-remotely.html>

TeamViewer.com (free for personal use)

<https://www.teamviewer.com/en/download/mac.aspx>

<https://www.teamviewer.com/en/res/pdf/first_steps_unattended_access_en.pdf>

<http://computers.tutsplus.com/tutorials/how-to-configure-a-mac-to-make-remote-su pport-a-breeze--mac-49922>

The hardway (but oh so much fun for the inner geek in you )

• Enable the iMac System Preferences -> Sharing -> Screen Sharing (make sure you have very good passwords on the user accounts on the iMac <https://www.grc.com/haystack.htm> longer and easy to remember & enter, is better than complicated & short <http://xkcd.com/936/>; good advice in general)
• Configure the home router where the iMac resides to port-forward port 5900 from the internet to the iMac. <http://portforward.com/>.  This is why you want good passwords, as the iMac's screen sharing port number is going to be exposed to the Internet, and 5900 is a well known port number, so there are script kiddies always trying to see if someone has exposed the port with an easy to guess account and password.  Chances are they do not know the username, but a good password just means it is that much more difficult to guess.
• Get a free Dynamic DNS name from No-IP.com, and then run the Dynamic DNS updating utility from No-IP.com on the iMac so that you have a name and not an IP address you can connect to (No-IP.com will require you to confirm you still want the free Dynamic DNS name once a month).
• From the Macbook use Finder -> Go -> Connect to Server -> vnc://the.dynamic.dns.name

There's an easy way, built into OSX (from, I believe, Yosemite). It is achieved through Messages and, rather than my explaining it again, you can read how to set it up (it's dead easy) here. I've used it myself to work on a friend's computer in Belgium (I'm in Spain) and it worked a treat.

I don't know if it's actually "Back to My Mac" that is built into Messages. All I know is that Messages offers the ability to take control of another Mac at a distance across the Internet. It is very easy to use, but also safe: it requires that permission be given for control to be taken over and that permission lasts only for that particular "session". No actual set up or complications with VNC; all that is required is that both Macs have Messages.

Is Back to My Mac the native program built into Messages?

Back-to-My-Mac uses a lot of the same components as Messages.  They use different ways of connecting.  They are "Both" included as part of the OS X El Capitan software.

Messages requires someone to accept your request to access their screen, or they have to offer you the ability to use their screen.  It has limited file transfer capabilities.  BUT, it does allow you to hold a text, voice or video chat conversation at the same time (although video is going to compete with the screen sharing bandwidth needs).

Back-to-My-Mac allows unattended screen sharing, as well as mounting the remote Mac's file system for doing file transfers over the net.  Of course nothing stops you from using Messages for text, voice or video chat in parallel to using Back-to-My-Mac.

Back-to-My-Mac is end-to-end encrypted for screen sharing and file sharing, as Back-to-My-Mac uses an encrypted tunnel between the 2 systems.

I think with Messages (but I'm not positive) that if you want the screen sharing encrypted, you need to access the Screen Sharing utility preferences and specify fully encrypted sessions.  You can find the Screen Sharing app in "/System/Library/CoreServices/Screen Sharing", if you want to launch it manually and set the Preferences.

Is Team Viewer, being a non-native program as effective and safe?

Sometimes TeamViewer.com is better at making a connection.  TeamViewer.com has been able to navigate more home routers than many other screen sharing utilities.  In fact I would choose this as my fallback utility.

The TeamViewer.com servers are ONLY involved in allowing the 2 systems to exchange network addresses, then the 2 systems establish a direct connection with each other.  All communications is end-to-end encrypted between the 2 systems.

Thanks for your help so far. I'm going to give at least one of these options a try.

Please try 2, as it really is a pain if the one-and-only method you get working fails while you are away.