[2.0.73] Multiplayer game list fails to load, shows JSON parsing error 520 instead

[ReTrooper]

Since about two days ago (Feb 11th) the list of MP games fails to load. This never occured earlier and I could join MP games the days before without issues.

Now I suddenly get the following message instead:

Code: Select all

Download failed (status code 520): failed to parse JSON response: Unexpected character (s) at ?:1

My OS is pretty old (Windows 7) and I suspect that it might be at least partially responsible for the issue, though I (should) have all available updates installed.

It is not purely my system causing the connection issue, since I am able to read the server list JSON in my browser (at multiplayer.factorio.com).

I attached the log file and a screenshot of the error message.

There are several suggestions for this (or a very similar) issue in this thread:

[Windows 7] Error trying login in game "InitializeSecurityContext failed: SEC_E_ILLEGAL_MESSAGE"

I have tried them all, but to no avail. My OS was up to date before anyways.

Via M45-Science: Factorio Server Browser I was able to figure out an address of a server and could successfully connect to it via direct connection in factorio. Hope this info helps to isolate the problem.

[Honktown]

I also have this issue. Yes I am also on Win7.

[Loewchen]

OP has this issue: 99521

[Honktown]

OP has this issue: 99521

I am in that thread. I am one of the people who applied the solution at the time, to success.

I know the chances of a resolution this time are "slim to none", but I ran into it the other day. It might've been the first time I tried Public Games since 2.0 released.

[DoctorLife]

Hi. Have same problem. All KB's installed.
It was fine a few months ago.

[eugenekay]

Heroku (Wube’s infrastructure provider) publishes a list of the Available Cipher Suites; this article was last updated April 17, 2026, which may indicate that a change was made recently.

There no longer appears to be any overlap with the Windows 7 Cipher Suite List, which will lead to a TLS negotiation failure. Microsoft has abandoned support for Windows 7 (released in 2009 - 17 years ago! Extended support ended in 2020 - 6 years ago), so an update to this list is unlikely to happen.

It is possible to bring your own TLS stack on Windows - this is the approach used by Firefox - but the developer must then assume responsibility for maintaining & distributing a Root Certificate Store, and the use of custom Root Certificates becomes much more difficult for all users.

The use of an Operating System which is currently supported by the Vendor would be a good idea.