Please take some time to peruse the headings below. You are likely find answers to your questions here. However, if you cannot find the answer to your question, please send us a note.

Why am I getting "Invalid URL String" error?
This error string was meant for developers' eyes only, but quite a few of our customers has seen it already. And yes, it is not a helpful error code.

Most DDNS providers require a HTTP GET command to update DDNS records. dDNS Broker constructs an URL based on provider's format and arguments supplied by the user in the DDNS Record Edit dialog box. For example, for DtDNS, dDNS Broker constructs the following URL:


This URL must be well constructed, otherwise we get the dreaded "Invalid URL String" error. In the example above, two HTTP parameters are supplied by the user: hostname, and password, and the third one, the IP Address is supplied by IP Monitor.

Now, what could go wrong here? (1) Extra leading or trailing white spaces, (2) Special characters in the password.

dDNS Broker is designed to remove extra leading or trailing white spaces. However, we recommend our users to be extra careful when copying parameters from DDNS provider's web site, and pasting to the fields of dDNS Broker's dialog boxes.

The special characters in the password field is a much common problem. The different parts of the URL string have different character sets requirements. Any character not included in that character set must be "percent encoded". The problem is, prior to v2.5 of dDNS Broker does not percent encode unallowed characters. This limitation is already fixed in dDNS Broker v2.5. However, if you use earlier versions of our application, then please do not use the following special characters in your passwords: "#%/:<>?@[\]^`{|}
Which dynamic DNS providers are supported?
The following dynamic DNS providers are supported. Providers marked with 6 suffix support IPv6 DNS records. If your favorite dynamic DNS provider is not on the list, send us a note to help us prioritize our support list.

Which dynamic DNS record types are supported?
Updates to the following DNS record types are supported:
  • A Record: An A or IPv4 Address record (also known as a host record) links a domain or hostname to the IPv4 address of a computer hosting that domain’s services.
  • AAAA Record: An AAAA or IPv6 Address record links a domain or hostname to the IPv6 address of a computer hosting that domain’s services.
  • MX Record: Mail Exchange (MX) records direct a domain’s email to the servers hosting the domain’s user accounts.
Please note that your service provider is likely to support a similar but potentially different set of record types.
How does dDNS Broker detect IP address changes?
dDNS Broker uses a proprietary algorithm to detect changes to your Mac's public IPv6 address.

dDNS Broker detects changes on your Mac's public IPv4 address by querying its own IPv4 address from STUN servers from all corners of the world. About 140 STUN servers are utilized.
Why does dDNS Broker not launch at system startup?
On Mac OS X there are a few types of background applications that start at system startup, with varying restrictions. The most elegant solution is a variant of dDNS Broker, designed as a preference pane application. However, such applications are not allowed to be sold through the Mac App Store. The applications released through the Mac App Store must run in a "sand-box" and hence their capabilities are constrained.

We indeed considered developing a preference pane version of dDNS Broker. If there is demand for such an application, we will be more than happy to develop it. What do you think? Please send us a note.
How can I launch dDNS Broker in recovery mode?
Sometimes, a user defined preference (like a service record) exposes a defect in dDNS Broker that causes the application to hang or crash. The problem is compounded if the engine switch was left at the "On" position, resulting perpetual application hang or crash cycles.

dDNS Broker supports "Recovery Mode". In the "Recovery Mode", the main switch is initially forced to the "Off" position. This mode allows the user to modify the preferences and isolate the offending one. You can start dDNS Broker in the "Recovery Mode" by holding down the command key while launching the application and keep it down for about five more seconds. You should see a "Detected Recovery Mode" notification.

At times, it is best to reset dDNS Broker preferences and start fresh - just as a fresh install of the application. Please refer to the Frequently Asked Questions (FAQs) item titled "How can I reset dDNS Broker Preferences?" for details.
How to recover from "Failed to initialize the application's saved data" error?
Unfortunately, due to a defect in our application v2.6 and earlier, some skip-level updates (like v2.4 => v2.6) can not migrate the database properly, which results in "Failed to initialize the application's saved data" error on relaunch.

The only way to recover from this condition is to reset the applications preferences (see the next FAQ) and import your DDNS update records, or recreate them.

We apologize for the inconvinience this defect may have caused and we promise to fix it in future releases.
How can I reset dDNS Broker preferences?
The easiest way to reset the application to "just installed" state is selecting the "Reset Preferences..." item from the status bar menu and following the instructions. However, if that option is not available, follow the instructions below.

  • Copy this path, excluding double-quotes, to clipboard: "~/Library/Containers/com.AppQuarter.IP-Monitor/Data/Library/Application Support/com.AppQuarter.IP-Monitor"
  • Select "Finder" / "Go" / "Go to Folder..."
  • Paste contents of the clipboard to the text box, and click on the "Go" button
  • Delete all three files in that folder. They all should have names starting with "PrefModel"
  • Restart dDNS Broker, and follow on-screen instructions
Note: You may not traverse the directory hierarchy manually to reach to the same folder, as path includes hidden folders.
Which third-party VPN clients are supported?
dDNS Broker's predecessor IP Monitor v2.4 utilized a set of heuristics to detect presence of third-party VPN clients. Hence, with that version of the application, we can only claim support of VPN clients we have explicitly tested with. IP Monitor v2.4 supports the following third-party VPN clients.
  • Tunnelblick v3.6.8beta02
  • Shimo v4.1.3
  • Viscosity v1.6.6
  • VPN Unlimited v3.1
However, dDNS Broker v2.5 has a proprietary algorithm to analyze some system data structures to detect presence of third-party VPN clients. This algorithm is less prone to imperfect VPN client implementations, hence we expect dDNS Broker to work with most popular VPN clients.

Please let us know if dDNS Broker does not work with your favorite VPN client. That will help us prioritize our development and test plans.