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Moving to next unit of Trailhead project, generates error "400 Bad Request"


This is to report an issue on Trailhead projects units.
The following error message is displayed when trying to go to the next unit of aTrailhead project.
400 Bad Request
Request Header Or Cookie Too Large

Screenshot of the web page displaying the error:
User-added image

Here is a sample URL that I was trying to access, does not when refreshing the URL.

Any help is much appreciated, thanks

Amit Chaudhary 8Amit Chaudhary 8
Pleae try to select next module from below link:-

All other module you can select from below link

Please let us know if this will help  you
@Amit Chaudhary 8
Thanks for your help, but unfortunately it does not work.

I tried again for a different unit of the same project, and still receiving error: 400 Bad Request / Request Header Or Cookie Too Large
for example :

Anybody else is having this issue?
Khoo KeongKhoo Keong
Yes I am facing this issue no matter which link I clicked.
Sue Maass 16Sue Maass 16
Yes, I got the same message this morning here. 

Anybody know the solution?
Stewart McNaughtStewart McNaught
After I manually deleted the cookies related to [Delveroper.Salesfoce.Com], I was able to relogin and proceed to the next module. 
Erin Peterson-CrockerErin Peterson-Crocker
I keep getting this error
Holger Dehne (HDE)Holger Dehne (HDE)
anything new in this topic? i get the same error for days now. is fine but every time i want to access trailhead, no matter where i'm coming from or what module/trail i want to take, i get the 400.
Holger Dehne (HDE)Holger Dehne (HDE)
after playing araound a bit i cleared my cache and deleted all the cookies in my chrome and... like magic... now it works again. thought it might help you too. Cheers
Jim Simon 3Jim Simon 3
I deleted all my Chrome cookies for the past week, because I was worried this might result in a loss of the points I earned, too.  I was afraid deleting all cookies would delete ALL my points.

Anyhow, the affected trail works properly again, and I didn't lose any points.  Thanks, Holger!
Bryan Lubic 2Bryan Lubic 2
After reading these responses, and not wanting to clear my cookies, I opened the link in a Chrome Incognito tab and it worked.