Update server connection error - Error ZLM01

I have just downloaded and

installed the app but on opening it freezes and after a few minutes I receive this error message.

Any thoughts? I have used the program before, but not for several months, and have never had a connection issue. 

Hi Ken,

Try doing a clean uninstall and installing again:

  1. Open up finder
  2. Hold the “Alt/Option” key and click Go > Library
  3. Open “Application Support”
  4. CTRL-click (or RIGHT-click) on the Zwift folder and move to trash
  5. Remove any Zwift folder from your Downloads folder
  6. Re-download the ZwiftInstaller and run again

Let me know how it works!


Hi Eric, 


Thanks for the quick reply, unfortunately the only message I get now is that there is an error during the installation. I am trying to put this on my iMac desktop computer. I have it installed on my laptop and it almost works. Instead of the message in my first post it asks me if I want to continue anyway and I can enter the training program. There are no issues after that. 

I have included the error message window below.


Any support is appreciated!




This is the message I am getting on my laptop. I am able to use the app, but I cannot see any other riders. Thoughts?

Hi Ken,

It looks like something is blocking Zwift from properly reaching our servers which is only reason why riders wouldn’t be showing (they’re sending the info to your local application).

Do you happen to have any kind of Firewall set-up? Either on your computer or on the modem/router?

I am also getting the same error message,I have Zwift installed on my Mac Mini, I am currently in China and without using a VPN I get the ZLM01 error. Using a vpn I can get through this first connection / update screen but then I cannot get the Mac Mini and my iphone to sync and use mobile lync to find my trainers. I have checked and my firewall is turned off.

Any suggestions on how I can get my Mac to talk to your servers without using a VPN?

I have the same problem as Ken FORD and getting the ZLM01 error message. I am also in China. Did anyone find a solution? Thanks


1 Like

Hi Zwift team, any fix for this? I’m also in China and get the same ZLM01 error. I can choose not to update and continue, but then I get “connection error” upon trying to log in. Please, help us find a solution.  Thank you

Exact same issue … please help

Hello guys who suffer ZLM01 and hello Zwift support team,

I have found how to solve error ZLM01. Here is a video about how to avoid ZLM01, which well described by Mainland Chinese zwifter xxxic who I sometimes race against. He is a great zwifter.
I understand Chinese Mandarin and I hope who try to play Zwift in China also understand the language, but if not, I can describe some. Anyway you may understand just seeing the picture without the language.
The problem is that the zwift updater for the Mac OS try to access google. His TCP/IP monitoring tool shows the Zwift Updater try to open connection to google.com, which is blocked by Chinese great firewall.
After seeing this video, I checked my zwift updater on Windows with some TCP/IP monitoring tool, but as for Windows version, it doesn’t make a connection to google server. So this problem is specific to Mac OS version of Zwift updater. My guess is the zwift updater employs embedded web browser component, and the component have some glitch that it unintentionally try to access google server in some circumstances.
The video describes how to use VPN tool to avoid the error, but it looks too complicated and too geeky. It’s much better if we don’t need this kind of hack.
I think if you remove unintentional access to google server, Chinese zwifter will have more easy access to Zwift.
Recent update included Chinese language localization, that’s awesome. And, with solving this ZLM01 problem on Mac OS, you can reach out more Chinese non geeky zwifter. Let’s solve this problem and I hope zwift to be more inclusive! Thank you!

Sadao Ikebe