Retrospect Error 530: Client not found

For many years I have used Retrospect for backing up our home computers. It's very important to have a thought-through backup strategy, that includes keeping more than one copy of your data, including at least one copy that is "off-site". If disaster strikes, such as your computer hard-drive failing, you wouldn't want to lose all your documents, photos and possibly emails.

This blog post is one of those "note-to-self" ones. I've stumbled across the same problem twice now, and I'd forgotten the solution from the first time around. So I make a note of the problem, and the solution, to help myself when the third time comes around, and anyone else who has hit the same problem.

If you're a regular reader of my blog but don't use Retrospect, please disperse: There is nothing to see here.

The Problem

Retrospect lets you have a main computer that you back up, but also a number of "clients". You install the Retrospect Client program on the client computer. Your main computer can then connect to the client, and include drives / directories from the client computer as another source location for backups. You can therefore back up multiple home computers from one master backup computer.

The problem is that, after installing the client and using it for sometime, the main backup process starts to say it can no longer see the client. Yet the client computer is online, responds to ping from the main computer, and you can browse files on shared folders on the backup computer. What's more, if you log in to the client computer, the Retrospect Client software appears to be loaded and running.

You get the error with code 530: "Client Not Found"

What's Gone Wrong

It turns out that my anti-virus software had added an extra virtual network interface on the client computer, so that it can monitor network traffic. Essentially it's a loop-back interface, with the IP address and subnet using one of the ICANN reserved IPv4 areas for local networks.

That means the client computer has (at least) 4 IPv4 addresses:

• 127.0.0.1 (localhost)
• the anti-virus virtual network address (in the form 169.x.x.x)
• the address on my home network (192.168.x.x)
• the public address assigned to our broadband connection by our ISP

As the client and the main backup computer are both on our home network, the backup computer should be accessing the client over that home network, and the client should identify itself with the home network IP (192.168.x.x). When it was first installed, it did just that.

However, at some point, all by itself, the client decided to listen instead to the virtual interface (169.x.x.x). If you open the Client application, you can see this unwanted IP address in brackets after the client name on the status tab. That means the client is not listening on the interface over which the backup will seek to open a connection. So the backup computer cannot see the client.

The Solution

So the solution is to force the client to listen on the home network inteface, 192.168.x.x. Happily, Retrospect provides a way to force a client to use a specific IP address (and hence interface). It's not in the user documentation for Retrospect, but it is on their website, so you'd find it if you search for it or stumble across a forum post that points there.

• On the client computer, open a command prompt with elevated privileges. (Start, type "cmd.exe", choose "run as administrator").
• Use the cd command to change to the Retrospect client folder, probably in C:\Program Files (x86)\Retrospect\Retrospect Client
• Run the command retroclient.exe /ipsave xxx.xxx.xxx.xxx to change permanently the IP address the client will use. [So, let's say your home network uses netmask 192.168.0.0/24, and the client computer is on 192.168.0.15, you'd run retroclient.exe /ipsave 192.168.0.15].
  • Obviously, this computer needs a fixed IP address. How to assign a computer on a home network a fixed IP address is beyond the scope of this post. You'd either:
    • Set up your home router to assign this computer a fixed IP in its DHCP settings
    • or use the network settings on the computer to assign it an IP address which is within the netmask range but outside the DHCP range.
• You may then have to tick the box "Protected by Retrospect Server" to re-enable the client, as Retrospect seems to disable the client when you make this change.

That should be it. You may also need to reboot the client computer, but you should now be able to back it up without the client disappearing from view.