[Fango]

Originally Posted by schlubby

I've got a couple possible workarounds. When I get a chance, I might PM the mods a fuller explanation, but here's what people can do right now:

"TL;DR" For users:
There are two possible workarounds:
1. go into your settings and turn off Javascript for OCC before you log in, and turn it back on afterward. The error is in a script that isn't needed. Note that turning scripts off is generally a bad idea, and can cause all sorts of other problems, so I don't suggest that you just turn scripts off and leave them off.
2. Only for people who know how to use Chrome Dev Tools: "Inspect element", then find and delete this element: <input type="hidden" name="vb_login_password"> before logging in.

"TL;DR" For OCC:
If you can edit the vBulletin HTML code at all, I think you can work around the issue by removing the *hidden* "vb_login_password" field from the template. It doesn't appear to serve any useful purpose (though it MIGHT be used in another part of the code I don't know anything about), and when I remove it from the page (using the Inspect Element tools), I'm able to successfully log in with Chrome.

My educated guess is that vBulletin was relying on unspecified functionality in a feature that was designed for the way browsers worked 10+ years ago. The code that breaks Chrome is broken in FF and IE11 as well, but in those other browsers, it fails in a different way (doing nothing) that doesn't interfere with the server-side login code.

Originally Posted by captaintrips

What a brilliant comprehensive answer. I can't say I understood much of it but I understood that you understand the issue and have provided a workaround. Thank you just isn't enough.

Yes, thank you very much for providing this solution, schlubby. Hopefully it works for everyone having this problem.

Fango