Have been having the issue with "An update error occured" when the Mac client tried to hit the patch server. Have been trying all of the posted fixed and finally I found someone with a solution that worked for me over in the Lotro Mac client forums... in short, for me anyway, Avast! Mac Antivirus Web Shield is the culprit. Once I added both patch.ddo.com and patch.lotro.com to my Avast! exceptions I'm back in game using the native Mac clients... FINALLY!
This is a duplicate of the posting in the thread:
"avast! virus protection prevents Mac Client startup - An Update Error Occurred"
This may be a more common fix (post Update 10) than the previous solutions.
If you use the avast! for Mac product, it will prevent the Mac Client from contacting patch.lotro.com and updating.
The end result is the "classic" error: "An Update Error Occurred."
In the System Preferences control panel for avast!, "Web Shield" is the culpret.
If you have it enabled, the Mac Client will not get started.
You can either "disable" Web shield completely, or select "Advanced" and add "patch.lotro.com" (HTTP) to the list of exclusions.
(For the Bullroarer client also add "moria.patch.lotro.com")
I assume that this issue will also occur with other anti-virus programs which scan web content.
If you are having the "An Update Error Occurred" problem, try disabling your anti-virus scanner. If it works, please report your results back to this thread!